Snakebite envenoming is a medical emergency which is common in many tropical lower- and middle-income countries. Traditional healers are frequently consulted as primary care-givers for snakebite victims in distress. Traditional healers therefore present a valuable source of information about how snakebite is perceived and handled at the community level, an understanding of which is critical to improve and extend snakebite-related healthcare.The study was approached from the interpretive paradigm with phenomenology as a methodology. Semi-structured interviews were conducted with 19 traditional healers who treat snakebite patients in two rural settings in Ghana. From the Ashanti and Upper West regions respectively, 11 and 8 healers were purposively sampled. Interview data was coded, collated and analysed thematically using ATLAS.ti 8 software. Demographic statistics were analysed using IBM SPSS Statistics version 26.Snakebite was reportedly a frequent occurrence, perceived as dangerous and often deadly by healers. Healers felt optimistic in establishing a diagnosis of snakebite using a multitude of methods, ranging from herbal applications to spiritual consultations. They were equally confident about their therapies; encompassing the administration of plant and animal-based concoctions and manipulations of bite wounds. Traditional healers were consulted for both physical and spiritual manifestations of snakebite or after insufficient pain control and lack of antivenom at hospitals; referrals by healers to hospitals were primarily done to receive antivenom and care for wound complications. Most healers welcomed opportunities to engage more productively with hospitals and clinical staff.The fact that traditional healers did sometimes refer victims to hospitals indicates that improvement of antivenom stocks, pain management and wound care can potentially improve health seeking at hospitals. Our results emphasize the need to explore future avenues for communication and collaboration with traditional healers to improve health seeking behaviour and the delivery of much-needed healthcare to snakebite victims. Many snakebites in tropical lower and middle-income countries are treated at the community level by traditional healers whose services are often accessible, affordable and offer care within the realms of local tradition and culture. A drawback of traditional care, however, is the associated delay or non-presentation of patients in need of antivenom and medical management at hospitals. We conducted interviews with traditional healers in two separate areas of rural Ghana to chart the socio-cultural context, perceived problems, treatment approaches, health seeking behaviors, and possibilities for future collaboration in snakebite treatment and management between hospitals and traditional healers. Healers described a holistic treatment approach, addressing physiological, psychological, and spiritual complications of snakebite. Healers reported high success rates with therapies ranging from herbal medicine to minor surgical interventions. Major factors precluding hospital health seeking of patients were identified as costs, poor accessibility, lack of antivenom and insufficient pain control. Gaps in clinical management are modifiable factors that, if improved, are likely to increase clinical health seeking. Our findings emphasize that traditional healers can provide a critical link between snakebite patients and hospitals, making their involvement crucial to the rural expansion of snakebite research and emergency care. Snakebite envenoming, designated a priority neglected tropical disease by the World Health Organisation (WHO), can cause serious and potentially fatal toxicity and disability to the human victims . DependiThe most effective treatment of systemic snakebite envenoming consists of rapid transport to a hospital where prompt administration of antivenom, and where necessary cardiovascular, respiratory supportive therapy and surgical debridement of necrosed tissue or even amputation can be delivered ,11,12. ITraditional medicine according to the World Health Organisation ‘refers to knowledge, skills and practices based on the theories, beliefs and experiences indigenous to different cultures, used in the maintenance of health and in the prevention, diagnosis, improvement or treatment of physical and mental illness’ . The preThe snakebite treatment repertoire of THs described so far in literature encompasses a variety of different practices ranging from the administration of topical and emetic herbal concoctions, snake stones, tourniquets, all the way to cutting and suction of the bite wound ,20,23,24THs can therefore serve as a gateway to charting the ethnic, cultural, social, and epidemiological dimensions of snakebite envenoming. This study seeks to comprehensively describe snakebite envenoming at the community level from the perspective of the traditional healer by means of interviews with THs in two regions in Ghana.Ethical clearance was obtained from the Committee on Human Research and Publication Ethics, Kwame Nkrumah University of Science and Technology and from the Medical Ethical Committee of the University Medical Centre Groningen, The Netherlands (CHRPE/AP/354/19). Written informed consent was obtained from THs after being briefed about the goals and the procedure of the study and participation was entirely voluntary. After completion of the interview, THs were offered between 10–30 Ghana Cedis  as compensation for their time and any transportation costs incurred .An interpretative paradigm with a phenomenological approach was employed as the study methodology. This approach elicited the stories of THs expressed through interviews. By studying the social and cultural variables that impact on practices in the management of snakebite and the interplay between these factors , we sougEchis ocellatus), the puff adder (Bitis arietans), the black-necked spitting cobra (Naja nigricollis) as well as the green and the black mamba   mostly by stepping on its tail. You could step on any other part of the body and it could be cool, but on the tail, you anger it.” TH9, Male“It can be related to a curse, if you are cursed, you can have a bite.” TH16, Male“They bite with reason.” TH3, Female“THs were nearly unanimous in their belief that all snakes are venomous, albeit to varying degrees. When shown pictures of five highly venomous snakes native to Ghana, some snakes were persistently seen as dangerous, whereas others were brushed-off as harmless.He [Naja nigricollis] spit, you can go blind and you can also die when it bites you.” TH1, Male“No, it [Bitis arietans] won’t bite, it’s the most foolish of all snakes.” TH4, Male“No, it’s [Dendroaspis viridis] not very dangerous.” TH16, Male“THs’ knowledge of traditional medicine and treatment practices in snakebite was almost exclusively acquired from predecessors  or from mentors (THs) external to the family through ‘apprenticeships’. Once a family member, mostly within the nuclear family, has the knowledge and skills to treat the diseased, the children are acquainted with the herbs and ingredients used to treat certain ailments. The children’s role is not insignificant, often being sent to gather the required herbs in the surrounding bushland.It’s [the knowledge] handed over from my great-great grandfather to my grandfather, through my father and to me, so I learned it from this lineage.” TH17, Male“My grandfather introduced me to the herbs, so anytime somebody came to the house with a snakebite, I was asked to go to the forest and bring the herbs and then my father will mix it with something […] to manage the patients.” TH1, Male“External mentorship and training within the family were either the sole source of knowledge or they were coupled to a divine calling. It is believed that traditional priests are gifted with the divine ability to follow the guidance of deities and spirits to treat victims who are afflicted with various ailments, including snakebite.The spirit just came upon me.” TH3, Female“The gods have called me to help society.” TH7, Male“Some claimed that there were occasional gatherings at which hospital workers and THs discussed health-related issues or where THs received treatment instructions. Some THs, particularly those stationed within or close to towns, reported to attend professional gatherings of THs for updates. Advice-seeking from senior mentors (THs) was also a source of updates. On the contrary, the practice of traditional medicine appeared to be subject to competitiveness as well, highlighted by a wide-spread reluctance to divulge the ingredients of concoctions and the claim that competitors may even be out to deceive others.There is a challenge amongst us [the THs], everybody wants to prove they are powerful.” TH4, Male“The request for more teaching and learning offered by the hospital was expressed as an opportunity for improving practices and deepening ties with the healthcare sector.I would like to learn from the hospital and add to my practices to improve on my practices and also get more knowledge about the treatment.” TH5, Male“It would be helpful if we had a good collaboration with the hospital.” TH7, Male“THs generally considered themselves to be well-known and trusted within their communities and beyond, also by healthcare workers in some cases. As illustrated below, THs can be central figures within the social and political constructs of communities, providing social leadership and counselling.“They [the patients] appreciate me so much and they, more or less they’ve taken me as a spiritual father and if someone has any complicated issue, aside snakebite, quickly, they come to me.” TH8, MalePatients were said to either present immediately after the bite or up to days, weeks or at most a month later. A recurring issue within the theme of health seeking was in fact the delayed presentation of patients at THs’ practices. Issues noted with regard to delayed presentation were the insidious nature of some snakebites, going unrecognised at first and later manifesting through symptoms such as swelling of the bite site, or the great distances victims had to cover in order to seek help. One TH noted that he travels outside of his community to ensure timely treatment of snakebite victims. The delay in health seeking was recognized as a problem and associated with worse clinical outcomes and death.It doesn’t really take days, because if it takes days, it will bring about mortality, yes.” TH3, Female“So the biggest challenge is that some don’t report early. Some don’t report so early, they stay in the villages for long, they come with very big ulcers.” TH3, Female“Snakebite was widely perceived as an acute emergency with potentially deadly outcomes.It doesn’t bite for you to leave; it bites to kill.” TH8, Male“Many snakebite consultations of THs were however not necessarily borne out of emergency situations. Traditional medicine was said to also be possibly sought in conjunction with or after treatment at the hospital. The primary concerns of patients were supposedly unsatisfactory treatment at the hospital, the high costs associated with the latter and neglect of spiritual aspects related to the bite.Here it’s not like a doctor where you go, if you don’t have money, you will not be treated.” TH1, Male“Some do go to the hospital and come back here, because the intensity of pain is too much. And others too come, because the swelling is getting intense.” TH2, Male“Some will abandon the hospital treatment and come to me for treatment, which of course is certainly cheaper as compared to buying anti-snake venom.” TH2, Male“The handling of money in relation to treatment and traditional medicine was suffused with symbolism and even taboos for certain healers. Money was reported to spoil the effects of traditional medicine and many preferred gifts or to be paid in kind  or even the manual labour of the patients over money.The medicine is not for sale, if I do collect money, then I’ll spoil it.” TH13, Male“It can be sheep, it can be goat, can even be a cow, depending on your strength, you the patient strength. Yeah, then plus 700 cowries.” TH12, Male“Nearly a third (6/19) of the interviewed THs indicated that the high costs associated with hospital treatment reduced its accessibility for patients and some healers even reported that patients struggled to compensate for the comparably affordable traditional therapies.The diagnosis of snakebite in the traditional medical setting, besides characteristic clinical symptoms, was said to be based on anamnesis, physical examination and consultation with dwarfs and deities. The reported differential diagnosis of snakebite only included scorpion bites. Causality was reported to be obvious in cases when victims brought the dead snake to consultations, but was more complicated in other cases.[I] press to see whether there is depression. Yes, try to see if the person is oedematous.” TH16, Male“If I apply that herb and if it’s bitten by a cobra, the site becomes dark, or if it’s any other type, the place swells up, or the contours become like that of a sugar cane.” TH4, Male“But if you really doubt the snake that bite you and the charmer is there, he can call the snake.” TH12, Male“I can detect the type of snake from the smell and the smell differs from snake to snake. The scent of the various snakes are like some trees, for instance, and then some ants, some big ants.” TH12, Male“In cases where a “spiritual bite” is suspected, which was most often believed to be related to the patient not responding to ordinary treatment, divine consultation was deemed necessary. Four THs who also served as fetish priests explained they were capable of such consultations, while three THs said they referred patients to fetish priests for such matters.I don’t do the consultation, but they’ll go and consult gods- I mean the fetish- to know what the person has done wrong.” TH12, Male“One healer even raised the possibility of determining a spiritual cause of the bite using the dead snake.Yeah, I can easily distinguish. And this is done by, if it is a spiritual I can easily see all the signs and symptoms, if it is a normal snakebite I can also see it, so the spiritual one, when it happens, I kill the snake, open the abdomen, and you will see that there is no intestines. If there is no intestine it means it was sent by a spiritual force.” TH1, Male“If the patient did not respond to treatment, this also raised the suspicion of a spiritual bite. In case the snake was neither brought, nor seen, charming of the snake, consultation with the ‘oracle’ or sniffing of the bite site were employed for diagnostic purposes.The traditional treatment repertoire discussed consisted of herbal concoctions, physical interventions, prayers and sacrifices. Concoctions were said to contain combinations of any of the following natural products: herbs “Yes, so what I use ‘Bosre’ [viper] for, the head of the ‘Bosre’, I use it to even prepare the medicine.” TH13, Male“Such concoctions are applied locally to the bite site or are ingested systemically either alone, with a meal (e.g. porridge) or with a beverage . The efficacy of ingested concoctions was explained by some through ‘neutralization of the venom’ or detoxification through emesis.Interventions that were frequently reported to be performed at bite sites included removal of the fangs (or invisible fragments thereof), incisions “I remove the teeth, I use a substance, like chewing gum, always starchy, then I will send it closer to fire and put it on where the snake bit the client and remove the teeth and most often, four teeth are only left in the system of the human being.” TH14, Male“This one [Naja nigricollis] is very venomous, very poisonous, so after the bite, you should apply a tourniquet. If you don’t, the venom will climb up and could cause some life-threatening emergencies.” TH3, Female“What I do most is that when they come with wounds, I go to buy gloves, so that I wear on my hands and take good care of the wound for them.” TH3, Female“Immediate washing of the eyes after attacks by black-necked spiting cobras was moreover recommended using plant extracts or urine.Right away, you have to urinate into your palm and then wash your eyes with it, fast, by the way.” TH10, Male“While wearing boots, gloves, other protective clothing and certain behaviours were identified as preventative measures against snakebite, a widely practiced method to prevent snakebite was the ingestion of herbal concoctions as a means of fortification against snakebites. Such concoctions are thought to prevent snakebites, render them less dangerous and to even cause death of any surrounding snakes.… I mean if you drink that medicine it fortifies you for at least six months, so within the six months you cannot have snakebite. After six months you will need to repeat the dose, so it’s like immunization.” TH13, Male“For certain procedures THs also cited contraindications that guided them in their practice. This suggests that a few THs have acquired some physiological and anatomical concepts similar to biomedical theories useful in avoiding the exacerbation of patient’s symptoms. Many healers, however, did not express such explanations.I use only the herbs, I usually don’t like using other interventions like making marks with razor blades, because probably the person might have- might be diabetic and those cuts may cause problems, or you don’t even know the problem that the person- the other sickness the person has, the other conditions- medical history of the person.” TH5, Male“Despite the general tenor of confidence in their own treatment methods, there were also some challenges acknowledged by THs.greatest challenge is when the whole leg is swollen and it’s dripping with fluid and all that, that’s the greatest challenge. Or when you see total weakness, the patient is like paralyzed and all that as a result of the bite, that is a great challenge too.” TH8, Male“[The] Yes, if it’s spiritual, it’s my limit. If the person also [becomes] anaemic, it’s my limit, I have to refer to the hospital.” TH13, Male“Referrals were moreover considered for tetanus shots, antivenom injections, management of cellulitis and infective complications or cases where mortality appears to be imminent to the healer.After seeing him [the patient], I refer apart from the tetanus, so that they can be checked for also other infections that may come up or that stuff.” TH5, Male“On the long term, snakebites were associated with ulceration of the bite site, persistent swelling and pain, wound infections, ‘shivering in the rain’, loss of teeth, rotten tissue, deafness, weakness, deformities and amputations.It can lead to amputation, if you don’t take care, they can amputate the whole leg.” TH13, Male“But even after the treatment, the leg was not straight. The mother’s leg, where the snake bit, was not straight again.” TH12, Male“Four THs acknowledged that snakebite patients had died while being on their treatment. Two healers explained that the deaths had spiritual connotations and the other two claimed that patients had not adhered to the prescribed treatment.Knowledge of procedures at the hospital ranged from tetanus injections, antivenom administration, blood transfusions and infusions to amputations. Nearly all (17/19) interviewees rated antivenom as being effective.Yeah, it [the antivenom] really helps and I believe it’s a very good remedy and if we are to rank it, it’s the best.” TH8, Male“Criticism of hospital therapies were primarily related to the belief that antivenom is only effective as an immediate therapy (3/19) but not on the longer term. Moreover, around half (9/19) of THs repeatedly emphasized that healthcare workers at the hospital did not remove snake fangs from the wounds.Antivenom is effective, but in the hospital they cannot remove the fangs, or they do not remove the fangs so they only give you the antivenom which will solve the problem immediately, but in later years to come, you feel the symptoms can resurface. For instance chills and then other things, symptoms.” TH16, Male“Collaboration and communication with health facilities was seen as important by most interviewees and many said they would welcome better relationships and more exchange of information. This applied to feedback on referred patients and to antivenom, the presence of which was mostly known through patients who attended clinics and returned.Some [patients] go and they come back to tell, ‘When I went, I had anti-snake venom’. Some also go and come and they tell ‘No, I didn’t have any’.” TH3, Female“The opinion that collaboration and improvement of ties between health facilities and THs is necessary was not shared by all, though. An explanation offered towards this stance was the distinction between ‘hospital-based’ and spiritual aetiologies of disease.Some of them are hospital-based. But the other diseases, that doesn’t need to be at the hospital. More especially diseases that have spiritual implications attached can be managed here, not at the facility level.” TH1, Male“We are parallel, they are working, I am also working. I don’t have anything against them, they don’t also have anything against me, but there is no way there is any connection where we need to really do anything too.” TH12, Male“Through interviewing THs in snakebite endemic communities, we tapped indigenous knowledge and beliefs on the subject and brought to light the concerns of healers and community members on the matter. Prior studies on health seeking and traditional medicine in snakebite have examined the subject mostly from the community or the hospital perspective ,20,39 foIt readily emerged from the interviews that communities where THs practiced experienced a high burden of snakebite. All THs indicated they had treated several snakebite victims in the year prior to the interview. In addition, numerous anecdotal reports about snakebite incidents, the detailed descriptions of treatment practices and the high proportion of THs (12/19) who had personally experienced a bite all suggest a high incidence. Community surveys are urgently required to corroborate these findings and to elucidate the reasons that a fraction of patients do not present to hospitals . The risFrom their own point of view, THs appeared to enjoy an uncontested status as primary healthcare providers within their communities, a valued prominence for most THs. Community surveys and hospital data from a neighbouring district and other countries showed that traditional medical practitioners were indeed sought in 40–63% of cases ,18,39. AIt could be deduced from the interviews that the process of health seeking was neither bimodal , nor unidirectional . Although THs were the first point of call in the village, this did not preclude subsequent visits to hospitals or the parallel use of allopathic medicine and traditional therapy, even when distances to hospitals were considerable. A major issue identified by THs was the delayed health seeking of patients after having incurred a snakebite. This observation underscores that bottle necks to seeking help, such as long distances and lack of transportation, are also frequently encountered in patient’s pursuit of traditional medical therapies. The relevant literature describes such obstacles as being more commonly associated with delays in seeking hospital care, whereas traditional medicine is thought to be easily accessible in comparison ,18,25,39Knowledge acquisition on snakebite therapies was almost exclusively from family members, as is common in the practice of traditional medicine ,24,30,42While biomedical treatment of snakebite is based on a syndromic approach , many THClostridium tetani [in vitro and in vivo anti-haemorrhagic activity has been demonstrated in a study on Bothrops atrox toxicity in Columbia [Similar to what other authors have reported ,24,39, tm tetani . Tourniqm tetani . The mosm tetani ,20,39. Nm tetani , albeit m tetani  and in vColumbia . MoreoveColumbia ,52.The explanations for some therapies were grounded in physiological and anatomical concepts similar to biomedical theories. Treatment was for example meant to ‘neutralize’, ‘drain’ or prevent spread of the venom, proving that many THs agreed with the biochemical concept of envenoming . A furthEchis ocellatus, a deadly and very common snake in West Africa, is estimated to lie between 12–20% in the absence of antivenom therapy [The high success rates and the alleged effectiveness of traditional treatment measures seem questionable at first sight if compared to clinical syndromes of envenoming and the morbidity and lethality of snakebites as reported in literature ,10,25,53 therapy ,26,53. B therapy ,54,55. A therapy . In this therapy . The int therapy .The research framework applied enabled the collection of qualitatively good data. Healers were interviewed in two geographically and ethnically distinct regions and considerable geographic spread of healers was achieved within regions, providing a large breadth of responses. The sampling methods aimed at including healers of different religious backgrounds, as well as those also active as fetish priests. Two thirds of all interviews were held at local homes or villages of THs, ensuring a high likelihood of unbiased responses.Nonetheless, we also acknowledge shortcomings. First of all, the targeted sample size of 30 THs could not be reached. Data collection was prematurely aborted at the end of March due to travel restrictions as measures against the SARS CoV-2 pandemic took effect. The decision to still proceed with the analysis was based on data saturation becoming noticeable. Secondly, interview quality was occasionally compromised through bystander commentary, interpreter bias and potentially also by the venue . In one instance the interpreter remarked that the interviewee was reluctant to reveal information for fear of reprisals or correctional measures following the interview.We found that the most important qualities of THs in relation to health system strengthening were (i) that THs seek greater engagement with hospital/health facilities to improve the outcomes for their patients, (ii) that their primary goal was therapeutic and not financial and (iii) their identification of long term snakebite sequelae that arises from prolonged contact with victims that is very rare with conventional healthcare professionals. However, this research also brought to light the following drawbacks of traditional medicine: (i) the misidentification of highly venomous snakes as being harmless, (ii) the lack of standardization of treatment methods, education and training, (iii) the potentially harmful treatment practices associated with delay in seeking clinical care (iv) and (v) the insufficient transparency about treatment practices and denial of responsibility for adverse outcomes.There are currently few channels of communication between THs and healthcare facilities to the disadvantage of patients, who for example go searching for antivenom in vain. This underscores the need for updating THs on the availability of antivenom while concomitantly improving its stocking, quality and affordability. Health seeking would likely improve as a result since antivenom was widely regarded as effective by healers. Besides improving the availability of antivenoms, clinical care requires effective pain management and wound care, which has a high potential of increasing clinical treatment adherence and health seeking at the hospital level. At the community level, training and education in first-aid practices should be offered to THs who are willing to participate. Healers and the general public are also likely to benefit from education campaigns explaining the behaviour of snakes, clinical syndromes of envenoming and the best possible conduct and first-aid measures following a bite. A combination of these efforts is urgently needed to increase health seeking of patients at hospitals and to reduce snakebite related morbidity and mortality.S1 Appendix(DOCX)Click here for additional data file.


Integrated single-axis force sensors allow an accurate and cost-efficient force measurement in 6 degrees of freedom for hexapod structures and kinematics. Depending on the sensor placement, the measurement is affected by internal forces that need to be compensated for by a measurement model. Since the parameters of the model can change during machine usage, a fast and easy calibration procedure is requested. This work studies parameter identification procedures for force measurement models on the example of a rigid hexapod-based end-effector. First, measurement and identification models are presented and parameter sensitivities are analysed. Next, two excitation strategies are applied and discussed: identification from quasi-static poses and identification from accelerated continuous trajectories. Both poses and trajectories are optimized by different criteria and evaluated in comparison. Finally, the procedures are validated by experimental studies with reference payloads. In conclusion, both strategies allow accurate parameter identification within a fast procedure in an operational machine state. In production, many manufacturing applications, such as process diagnosis and quality assurance, or adaptive process control for milling, grinding or thermo-smoothing, require in-process force measurement, where, in particular, the measurement of spatial forces and moments in 6 degrees of freedom (DoF) is requested . As one Compared to commercial 6 DoF force/torque transducers (FT sensors), which are mounted close to the TCP, the new measuring system does not reduce usable workspace, causes no restrictions to spindle mounting and is also less expensive. Compared to a drive current based force measurement in spindle drives, it is far more accurate  and reqMachine-integrated force measurement solutions have been studied since the beginning of force measurement and are outlined in a detailed state-of-the-art overview in . In shorInstead, for the presented moving sensor system that is the end-effector of a parallel kinematic machine tool, a real-time capable measurement model, which runs within the numeric control system, is essential. As shown in ,2, an acNevertheless, some of the model parameters, such as mass, centre of gravity and inertia, can change during machine usage, for example through a workpiece or tool change, and need to be re-calibrated. These parameters shall be found using identification procedures, which are the focus of this paper. Referring to parameter identification, many works exist for the identification of rigid body dynamics for serial kinematics ,17,18,19As a new contribution, this work presents a one-step calibration procedure that allows the parametrisation of the measurement models first presented in , which aA hexapod-based end-effector is one of multiple options to integrate force sensors into hexapod structures and kinematics, which can be classified into not moving and moving rigid sensor frameworks as well as kinematic-integrated sensors. However, every model needs a parametrisation and to make the promising results of  availablFor all approaches, the parameters contain sensor positions and orientations  and sensor zero offsets (6 parameters). Additionally, for the focused moving rigid bar structures (setup 1b), mass, centre of gravity and inertia of the framework (10 parameters), as well as its actual pose, velocity and acceleration in real-time, are included. Moreover, additional parameters need to be introduced to include influences concerning the sensibility of force sensors towards lateral forces, torques, elastic structure deformation or temperature effects.The measurement model in the current form was first presented in  and is sThe sensor forces are transformed to Cartesian space using the geometric Jacobian The platform pose Numeric differentiation of Finally, this leads to the measurement model in its canonical form, with Here, For the present setup, these are sensor zero offsets According to the rigid body assumption of the end-effector, the force measurement is expected to be independent of the platform position, Equation . Howeverrdinates . Ref. [2Now, the effect is compensated for by only two parameters In fact, platform deformations resulting from platform joint forces not only occur at position changes but also at orientation changes. Neglecting these influences leads to the incorrect identification of mass and centre of gravity by quasi-static measurements, as shown below. As the orientation is part of the rigid body gravity model, Equation , a compeEquation , as an eEquation (14)fK4=Again, a transformation to Cartesian shows that the parameters can be reduced to the two most significant influences For this notation, an axis based format—here the Gibbs vector—needs to be used. A change of the Jacobian due to platform deformation can be neglected.In conclusion, by those four parameters, Alternatively, by inserting joints ,15 or flBesides process force measurement and control, structure-integrated force sensors can be used for parameter identification: As mass, centre of gravity and inertia of the end-effector can change during machine usage, for example through a workpiece or tool change, a fast and easy procedure for identifying these parameters is required, which should last less than Equation .Since friction and stick-slip effects can be neglected for the sensor placement in the rigid end-effector without joints (setup 1b), an identification from quasi-static measurements is possible: Doing this, the 10 parameters, platform mass Equation , is not Below, a linear identification model of the form6fq=AuisThe identification procedure can be performed with the non-linear model, Equation , by calctor L(ω) ,24(20)ITogether with the measurement parameters, this gives the linear form for one dataset Equation  K˜ is K˜Equation  K˜ is(2Stacking ov(fq)−1 . The weiIn contrast, parameter scaling is still required to obtain meaningful and comparable singular values for the next steps model analysis and optimisation as well as improved convergence. With the scaling matrix anges to (25)fˇq=lth column of For the choice of umn of A (26)hl=|An estimate of the global standard deviation of the regression problem can be obtained from the tatistic ,26(27)sGenerally, only those parameters that are modelled are identifiable, stimulated by the exciting trajectory (sensitivity), and that can be distinguished from each other (linear independence). Therefore, the optimisation of the parameter set and the optimisation of the exciting data points or trajectory parameters, respectively, are the two major steps in identification preparation. The parameters can be grouped in identifiable and unidentifiable parameters as well as parameters that are only identifiable in linear combination, expressed by a new parameter. QR or singular value decomposition of eter set .For the end-effector, different models are proposed for identification with different parameter sets and properties . IdentifEquation , and modEquation , includeFor all static models that neglect a modelling of orientation-dependent force errors models 0–2), the parameters , the parIncluding orientation-dependent force errors in the models always leads to a correlation of the error model parameters to the rigid body parameters, mass and centre of gravity, for quasi-static measurements since both parameter sets can only be excited by inclinations. When modelled by rotation matrix, Equation , the parIncluding orientation-dependent force errors, based on a different orientation representation, leads to the model 4, Equation , and modEven though models 0–2 are valid and contain fewer parameters, a structural rigid body approach using parameters with physical meaning is advantageous for a second reason: as Finally, models 8 and 9 include all error compensation parameters for dynamic identification, where model 9 uses fewer parameters  right.For a symmetric platform without accessories, some centre of gravity parameters In conclusion, models 5 and 9 provide a full error correction with minimal parameters and are chosen as the basis for further steps in the evaluation of quasi-static and dynamic identification procedures, respectively.In order to optimise poses and exciting trajectories, criteria are needed that can be defined on the basis of the regression matrix For quasi-static identification measurements, several poses are approached in the workspace and, at each pose, a set of force samples is taken in a stationary condition. The ability to wait until dynamic effects extinguish, and to average over many samples, leads to a higher data point quality for quasi-static measurements when compared to dynamic measurements. At the same time, the data points are independent so that every data point is valid; the data do not need to be cut and, generally, fewer data points are acquired, which is advantageous concerning memory and processing time of the regression. Still, the measuring time is very high and the inertia cannot be identified.Depending on the model, a minimum of m = u/n poses is required, where an overdetermined measurement including approximately 10 times more poses than necessary aims to obtain regression results with acceptable uncertainty. The choice of the correct poses is crucial for good identification results, where different parameters are excited by different poses: The identification of Equation , respectEquation , requireOptimising the pose set by selecting the most sensitive poses avoids redundancies and, in total, reduces both poses and measuring time, significantly. Basically, two approaches are available to optimise the dataset: As the data points are independent, poses can be added randomly until the chosen criterion saturates. Alternatively, starting from a generated good dataset, poses can be removed as long as the chosen criterion does not change significantly. Here, the latter approach is performed using the criteria shown in Algorithm 1: Selection of optimal poses using criteria of   // Create a set of valid posesfortobydo  fortobydo   fortobydo    fortobydo     fortobydo      fortobydo       ifis_valid) then                   // Reduce from n to r optimal poses  fortodo     fortodo                  This optimisation reduces the measuring time from 21 min for 480 poses to 81 s for 30 poses , which meets the requirement of a fast measurement in production breaks and, at the same time, realises an over-determination factor of 12.8. Further, the algorithm can be run until criteria . A reducAll criteria reduce the data set to 30 valid poses. As expected, poses with high absolute position values and large inclinations are preferred, whereas centred poses and poses with small inclinations are neglected , which are connected to a local EtherCAT-Client EK1101  at the end-effector platform, a fast and synchronous data acquisition of the forces is realised. The oversampling functionality allows a data acquisition rate up to 100 kSamples/s (10 s) that is used for 100 times averaging during a task cycle of 1 ms. Further, strut positions and velocities are acquired synchronously from a Sercos II drive bus, where velocities are differentiated to accelerations numerically. Finally, filter times of force and acceleration are adjusted to obtain a synchronous data acquisition, where the differentiator delay needs to be taken into account. Details of data acquisition and measurement results, for example, during a milling process, are presented in [For the exciting trajectory, two approaches are presented: a manually created trajectory and an optimised trajectory based on periodic functions. The model is so simple that the individual parameter sensitivity with regard to specific movements can be estimated by examining the equations, compare Equation , EquatioThis leads to a trajectory, as shown in Optimising a trajectory, on the other hand, requires criteria that are defined in For every DoF follows: ,30(34)iThe analytical availability of the derivatives is advantageous, as they can be used to filter the usually noisy velocity or acceleration measurements. Depending on the angle format, Further, the trajectory must be kept within valid bounds during optimisation. Basically, the hexapod movement is limited by strut lengths, velocities and accelerations, passive joint angles and singularities. Owing to the specific configuration of the hexapod , limited workspace coordinates are sufficient to avoid critical joint angles and singularities with certainty for the present kinematic, as long as they are not chosen very close to the workspace border. Velocity and acceleration limits can also be expressed in workspace coordinatesAltogether, this approach significantly improves optimisation speed as it avoids the calculation of the inverse kinematic, differential kinematic and validation algorithms inside the optimisation problem. At the same time, the remaining workspace stays large enough to house an optimised trajectory.N is the order of the Fourier series and needs to be chosen beforehand. As the trajectory can be centred in the workspace due to machine symmetry, the parameters fmincon optimiser for constrained non-linear minimisation), show the best results using the ‘active-set’ solver, D- or N-optimal criterion and third to fifth order trajectories, such as those presented in Looking at the parameters, the trajectory consists of When comparing the measured accelerations of both trajectories , the manAs a final step, the identification procedures and exciting poses/trajectories are validated and compared by the application and identification of benchmark payloads . In detaFor the dynamic trajectories, the global standard deviation More details are shown in It should be noted that a correct physical representation of the parameters is not the main focus of the identification procedure. In fact, all model parameters together must allow an accurate force measurement after calibration. Details on accuracy and precision in practise for quasi-static, dynamic and process force measurements with the end-effector setup are presented in . All ideStructure-integrated force measurement is an accurate and cost-efficient alternative to classic force measurement in 6 DoF. To compensate for machine internal influences, such as dynamics, a measurement model is essential. Depending on the measuring task, classic solutions using FT sensors at the end-effector also require or benefit from a measurement model. However, every model needs a parametrisation that, in this case, both determines the measuring accuracy and, furthermore, can change during machine usage. Following modelling and model analysis, two methods are presented to identify these measurement model parameters, which run in a fast and easy procedure, in an operational machine state and do not require any additional knowledge or setup-efforts from the machine user. Where quasi-static identification measurement is based on data acquisition in stationary conditions at several poses, dynamic identification measurement is based on highly accelerated movements while taking samples continuously. Both methods are applied to the hexapod-based end-effector with integrated force sensors and are optimised to find the most significant measuring poses and the best most exciting trajectory, respectively. By the application and re-identification of reference payloads both methods are validated and compared. In conclusion, all of the presented procedures allow for an accurate determination of the model parameters with relative deviations to the theoretical values that are, in most cases, significantly smaller than the maximum error of


Understanding the symptom and illness experience of children with advanced cancer facilitates quality care; yet, obtaining this understanding is complicated by the child’s developmental level and physical and psychological health factors that affect communication. The purpose of this study was to describe the symptom and illness experience of English- and Spanish-speaking children with advanced cancer as described by the child and parent. We conducted hermeneutic phenomenological, descriptive, and interpretive interviews with eligible children and parents. The interdisciplinary research team analyzed transcripts hermeneutically until consensus on theme labels was reached. Four themes and associated subthemes were identified from the interviews of the 10 child–parent dyads: 1. symptoms disrupt life , 2. isolation , 3. protection, and 4. death is not for children. Children and parents readily described the impact symptoms and cancer treatment had on their lives and relationships. These findings underscore the salient aspects of daily life disrupted by cancer. With a deeper understanding of symptom burden and its interference, relationship and communication implications, and anticipatory grief, the treating team may better optimize care for children and their families living with advanced cancer. The symptom and illness experience for pediatric patients with advanced cancer is an integral component of comprehensive cancer care. Suffering caused by symptoms such as nausea, vomiting, and fatigue, as well as symptoms limiting activities due to limb or central nervous system dysfunction, is common in children under active treatment or supportive care for advanced cancer. Concerns about eventual outcome of the cancer and its treatment cause additional suffering for both patients and their families.Communication of these health-related concerns is complicated by the child’s developmental level, physical and psychological health status, current distress level, and patient–caregiver relationships. Consequently, pediatric clinicians may need to rely on various resources and skills, as well as collateral information, to inform their interventions.Proxy assessments are often garnered from parents and treating clinicians, aiming to complement the child’s self-report. Agreement between reporters may vary depending on factors such as the particular symptom domain assessed, the individual rater, and patient–proxy relationship characteristics ,2,3. RatThe context in which the symptom occurs may also be relevant. The meaning of an individual symptom and its impact on daily life may vary depending upon other symptoms occurring simultaneously. Culture may impact symptom expression ,9. Few sStudy participants were recruited as part of a larger study designed to characterize the symptoms of pediatric oncology outpatients over the previous two days and to evaluate the association between child reports and proxy ratings . EligiblOnce participant consent or assent with parental permission, as age appropriate, was obtained for participation in the main study, children and their family caregivers were invited to participate in the interview portion of the study until data were saturated. Interviews, conducted by the bilingual research coordinator, took place separately, but as close together in time as possible, so that patients and their caregivers did not discuss interviews with each other before both were completed. Interviews were conducted face-to-face in the outpatient clinic. On study conclusion, family caregivers were reimbursed for parking or transportation expenses and the child received a $10.00 gift card.The children’s demographic and clinical information were collected from the electronic medical record and by child report. Family caregivers provided their own demographic information.Hermeneutic phenomenological, descriptive, and interpretive research methods guided the study . These rChildren were asked to describe their experience with their diagnosis and symptoms. Caregivers were asked to describe their child’s symptoms. The interview questions are detailed in Analysis of demographic data was descriptive, with medians and percentages, as appropriate. For the interviews, as is usual with hermeneutic phenomenological designs , analysiProcedures to ensure scientific rigor included having the analysis conducted by three researchers. Theme labels and passages were reviewed until consensus was reached. While verification of the theme labels with patients and parents would have been ideal, half of the patients were no longer alive by the time data analysis was completed. Interviews were conducted until no new themes emerged and data saturation was reached, meeting the standard criterion used in qualitative research .Interviews occurred with 10 children and 10 family caregivers. All caregivers were the child’s parent. Clinical and demographic data for the ten interviewed children and their family caregivers are displayed in symptoms disrupt life, 2. isolation, 3. protection, and 4. death is not for children. While descriptions of content were the same for children, adolescents, and their parents, children’s descriptions differed by their developmental level and sometimes were affected by their diagnosis. Younger children gave shorter, more concrete descriptions than adolescents and parents. Notably, similar themes were found regardless of participant ethnicity or language of interview.Four themes were identified from the interviews of the children, adolescents, and their parents: 1. Parents frequently described symptoms as a path to diagnosis. The initial symptoms led parents to believe that something was wrong with their child, thus beginning the path to cancer diagnosis. The mother of a 9-year-old daughter noted,“She would wake up in the middle of the night and she would cry, she would scream, she would say her arm hurt, her leg hurt, she was tired, she slept all the time and she just wasn’t herself. And you know, and then you are telling them look, a child that wants attention doesn’t wake up at one o’clock in the morning screaming at the top of their lungs, that they are hurting. There is something wrong with them.”The mother of a 10-year-old boy noted,“You know he started losing weight, appetite, which we just thought that was, he was a picky eater, he didn’t want to eat, but, you know, we look back now and we think, well, that was a sign; we just kind of ignored that … we didn’t realize that was one of the symptoms until we looked back …”In some cases, symptoms were described primarily as the past path to diagnosis, with few current symptoms. For others, symptoms that had led to diagnosis had reoccurred and/or were ongoing.Life is disrupted since the cancer diagnosis described the presence of physical symptoms and emotional distress that limited activity, which then created more distress. However, it was not just the symptoms but the impact these symptoms had on the child that made life different.The mother of a ten-year-old boy said:“OK, his major symptom is pain, obviously. Umm … back pain was his major symptom and leg pain … the point of that is it limited his walking, limited his activity … limited his playing with other kids … so it limited everything, really.”Symptoms and their meaning in terms of the illnesses were discussed by parents who noted, for example, that their child could not “carry on a normal life” because of incapacitating symptoms or that their child would not be able to attend college.Life was also disrupted by psychological symptoms. A 12-year-old girl poignantly described the distress linked with her symptoms as:“Well pain, as in headaches, no. But pain, as in of the heart.”Life disruptions included major losses and associated psychological symptoms. The mother of a 15-year-old boy said:“It is just that he gets angry because he thinks … we overprotect him, right? But at the same time he gets sad because he wants to, like, for example … he was there at school, he likes American football a lot and he cannot [play].”The children and their parents described the child as feeling different and no longer normal. A 15-year-old boy noted he felt,“Bad, sad. Because I cannot do anything … Well, like a normal child.” He also said, “Sometimes I am not myself; I am not the same person.”Children and parents expressed that other people may not understand the child and what the child is going through, leaving the child to feel alone and isolated. The mother of a 10-year-old boy remarked, “… Now he can probably go to school, some, but he doesn’t want to, because now he thinks he’s labeled again…”Families were forced to endure separations from family and friends, which affected relationships.A 9-year-old girl noted,“Because he [dad] is always home trying to take care of my sister, and my momma has to stay out here with me so she can like be here to tell the doctor all the information cause dad’s home working trying to make money … I wish he would like come out here and stay with us until December, but he can’t cause he’s working and has to take care of my sister because she’s going to school.”The unpredictable nature of the child’s course also impacted family relationships. The 42-year-old mother of a 15-year-old son commented that,“He (brother) never knows who’s coming to get him from school, like today … I said we may or may not be home.”These separations were particularly important because of the importance of support of and for family and friends. Parents, children, and adolescents each compensated by optimizing the available support. One 9-year-old girl stated: “I try to help out if my mom is upset or if anyone is upset, I like try to help them feel better.” She also described caring for other children who are sick: “I try to care about other people, help a lot of people and try to give them spirit to not give up.”Potential for harm led to various ways to try to protect children. The mother of a 9-year-old son who was physically active prior to leukemia noted:“I am scared about him. They told me that he had hurt his backbone, fractured-so to also not let him run because one fall or something would hit him badly-harm him.”Another mother reflected on how she protected her son by limiting information.“Well, he took it a little bad … he does not know how severe it is … because I have also not wanted to tell him because, well … the more sick [sic] he is going to get or get sad; I did not want that. He hardly asks anything.”Children limited information disclosure to parents, possibly as a means of protecting their sense of normalcy and perhaps as a means of protecting their parents. The mother of a 10-year-old boy noted,“I think he hides a lot. … He didn’t tell us how, how bad he was hurting cause [sic] he didn’t want to feel different, or to look at him different.”Finally, death is not for children reflects some parents’ fear and reluctance to discuss the diagnosis or prognosis with their child, although some of the children were clearly aware that they could die.The mother of a 9-year-old daughter said:“Well, when she started asking me questions about dying … You know, she could die from this. Just the thought of her, I mean, she didn’t want to die. You know, she knows, ‘I’m going to heaven, I know that, but I don’t want to die.’ Just stuff like that … You never want to try and take any kind of hope or anything away from them.”In a few cases, parents did not allow the child or adolescent to know their diagnosis. The mother of a 12-year-old daughter stated:“But she does not know, she does not know with full knowledge. Why? Because I think that I, as a mother, see that knowing certain things at times, instead of helping us, it can lead us to like “Why should I continue, why should I fight?’ Because like, what I feel like I am limiting her …”The discussion of death was primarily from parents. A mother noted that one of her 15-year-old son’s “new friends” from the hospital died two weeks before this interview, although the son did not mention this friend when interviewed. Despite parents’ attempts to protect their children from thoughts of death, some children discussed their awareness of death and prognosis. One 17-year-old boy described being unable to finish the year in high school, not seeing his friends, and added,“It’s either this or a blunt way to put it, it is six feet under.”symptoms disrupt life, isolation, protection, and a fear and belief that death is not for children) reinforce the scope of health care needed for symptom management and might suggest related structured clinical interview assessment domains (see Although specifically asked about symptoms, patients and parents focused primarily on the illness experience rather than the symptoms themselves. Potential reasons for this are multiple and bear further study. Some children and parents might believe that treatment-related symptoms, since transient, need to be tolerated, while others might believe symptoms were immutable, given their limited experience with aggressive symptom management . Others ains see .Notably, similar themes were found among participants, regardless of ethnicity or language of interview, although data were limited due to the small number of participants. However, behavior and beliefs, identity, daily life, coping skills, one’s life story, values, world view, and confrontation with death were all touched by illness and its symptoms.The broad impact of symptoms beyond the physical has been noted by another investigator who has coined the term “feeling states” to better represent the impact of cancer and cancer symptoms on children and adolescents ,14. Our Relationships were focal to the illness experience. Study participants described both negative and beneficial impacts, suggesting an opportunity for professional assessment and intervention. Giving and receiving support from family and friends were described as important coping elements and were psychologically beneficial. Bereaved parents of children who have died of cancer have similarly reported psychological benefit from reciprocated social support . ClearlyCommunication challenges were noteworthy. Several studies have documented a difference in symptom reports between parent proxy ratings and the child’s self-report ,16,17 ofChildren and adolescents described withholding information about their symptoms from their parents, essential information needed for treating symptoms. Withholding information from parents may contribute to discrepancies between caregiver proxy reports and child and adolescent self-reports of symptoms ,2,3,11. Fear and belief that death is not for children was discussed exclusively by parents, despite the finding that some children demonstrated death awareness. For children with a potentially terminal illness, incomplete communication may lead to unnecessary fears and/or missed opportunities for therapeutic interventions. This “need to protect” or rescue is a fundamental human behavior for families. However, neither parents nor children are capable of protecting the other from disease progression, death, or symptoms. Moreover, parents and children discussed anticipatory grief. This finding suggests that initiating conversations related to anticipated losses and the possibility of death, though difficult, may provide psychological relief.Data limitations include the small number of informants from only one healthcare site, the predominance of male patients and female caregivers, and the relatively high educational and income levels of parents. These factors may limit the applicability of these findings, although the themes were common to all 10 dyads.A number of strengths are also important. Children had diagnoses that were typical of the pediatric population. Both English- and Spanish-speaking participants were included, allowing people to express themselves in their first language. Twelve of the 20 interviewed were Hispanic. Finally, the rigor of the study methodology was high, using established standards, including translation and back-translation of the Spanish interviews and validation of the analyses by the research team.The perspective of patients and parents is important to guide assessment, discussions, and treatment. A potential semi-structured interview guide is provided in Insights offered by these children and parents highlight the importance of effective symptom assessment and control, as well as the broader understanding of cancer and its impact on children and their families. Potential reasons for differences in symptom reports between children and their parents have been elucidated. Often these reasons reflect wanting to protect one another or themselves and to maintain some degree of normalcy. Further research is needed to develop the elucidated themes and associated interventions to improve the symptom and illness experience for children and their families living with advanced cancer.


As the novel coronavirus (COVID-19) pandemic continues, frontline nurses caring for COVID-19 patients are experiencing severe fatigue and mental stress. This study explored nurses’ adaptation process in caring for COVID-19 patients and examined how nurses interact with the phenomenon using a grounded theory approach. The study aimed to develop a substantive theory and provide basic data with which to develop intervention programs that can support nurses caring for COVID-19 patients. Data were collected between 7 August and 31 October 2020, via face-to-face in-depth interviews with 23 nurses who had been caring for COVID-19 patients for six months or more at a nationally designated COVID-19 hospital. Sampling was started purposively and continued theoretically. Data analysis, performed using the method proposed by Strauss and Corbin, resulted in 13 main categories, the core one being “growing as a proficient nurse alongside comrades on the COVID-19 frontline”. The study’s results identify the nurses’ adaptation process in caring for COVID-19 patients and their reactions to the circumstances around it. Ensuring that nurses can systematically cope with emerging infectious diseases requires regularly providing them with basic education on caring for patients with such diseases and strengthening professional education in order to develop nurses specializing in them. This study also recommends that a support system for work and childrearing be developed. In 2020, the world faced the crisis created by the novel coronavirus COVID-19) pandemic. By early March 2021, the global number of confirmed COVID-19 infections totaled approximately 117 million, with approximately 2.6 million deaths, and the number of cases continues to increase 9 pandemi. AirbornNot only are the frontline healthcare professionals who care for COVID-19 patients experiencing anxiety and depression at clinical levels ,4,5,6, bHowever, COVID-19 is different from previous infectious diseases. The COVID-19 pandemic has created worsening shortages of nursing staff, which have become increasingly serious . Nurses Understanding the adaptation processes of nurses who are caring for COVID-19 patients requires us to examine how they interact with the caring experience. This will allow us to define the important conditions occurring in their adaptation processes and determine how nurses adapt over time [Grounded theory is a methodology used to identify the problems shared among group members experiencing a specific phenomenon and to explore the psychosocial process in depth. It is based on symbolic interaction theory, which posits that human behavior is determined through interactions with others . As otheAccordingly, this study aimed to develop a substantive theory and obtain an understanding of nurses’ adaptation processes in caring for COVID-19 patients by examining how these nurses cope and adapt using a grounded theory approach. We hope to provide the basic data needed to develop intervention programs that can support nurses who are caring for COVID-19 patients.This qualitative study explored the adaptation processes of nurses engaged in caring for COVID-19 patients by applying the grounded theory approach proposed by Corbin and Strauss .The study’s participant selection criteria were as follows. Participants had to have experience working as a nurse at a healthcare institution for at least one year and caring for COVID-19 patients at a nationally designated COVID-19 hospital in the negative pressure ward for at least six months; they also had to be informed about the study’s purposes and procedures and give voluntary consent to participation in the study. Study participants were selected using a theoretical sampling technique. Theoretical sampling is a data collection procedure used to develop concepts and themes from data, in which locations, persons, and events are sampled to identify the relationships among the concepts, confirm diversity, and maximize the chances of developing concepts in terms of properties and dimensions . In thisn = 8, 34.8%) of nursing experience; this group was followed by those with six to nine years  and 10 to 19 years . The mean years of nursing experience was 8.91 ± 5.43. Fifteen (65.2%) participants were unmarried, and four (17.4%) were married and lived with their children. Twenty (87.0%) participants were staff nurses, and the remainder were charge nurses. Regarding education level, 21 (91.3%) had a bachelor’s degree, and two (8.7%) had a master’s degree.The 23 participants were all female. Twelve (52.2%) participants were in their 30s, the largest age group, and the mean age was 32.34 ± 5.16. The largest share of nurses had three to five years  appropriate for the situation. To create an atmosphere in which participants could talk comfortably, each interviewer started with small talk and began the interview only when the participant appeared to be comfortable. During the interview, the interviewer avoided being critical or interpretive of the participant’s statements to preclude bias caused by the interviewer’s preconceptions. Additionally, the interviewers made detailed field notes on participants’ behaviors, facial expressions, tones, and other factors. After each interview was over, the interviewers wrote memos about anything they considered notable and their feelings during the interview; these notes were used as supplementary data during the analysis. All interviews were audio-recorded with the participants’ consent, and the recordings were immediately transcribed by two research assistants. The researchers confirmed the accuracy of the transcribed data by comparing each transcription with the associated audio recording in its entirety. Data collection was terminated when it was determined that theoretical saturation had occurred—when no new meaningful data were being observed, and no new categorical properties or dimensions were being identified.Following the grounded theory methodology proposed by Corbin and Strauss , data anTo ensure the rigor of the study findings, the researchers made efforts to increase their truth value, applicability, consistency, and neutrality, as suggested by Guba and Lincoln . SpecifiThe study was approved by the institutional review board (IRB) of the institution with which the researchers are affiliated (IRB No. 1041478-2020-HR-025). Prior to conducting the interviews, the interviewers informed the participants about the study’s purposes and procedures and said that the interviews would be audio-recorded. The participants signed a written consent form and were informed that the interview content would be used for research purposes only and anonymized, and that they could terminate their interview at any time. They were also informed that all data would be saved in a password-protected computer designated by the researchers and that they would not be used for any purpose other than for research. The participants were further informed that the data would be discarded after the study findings were reported. The participants were given a small gift as an expression of appreciation.Categorization of the interview data through an open coding process yielded 47 subcategories and 13 higher-level categories see . The relI didn’t want to care for COVID-19 patients and didn’t know how to care for COVID-19 patients…When severe patients were suddenly assigned to me in the ward, I had to make a phone call to another ward to borrow a CRRT  machine. I received an order to perform ventilator therapy when I was not even ready to prepare for suction, and honestly, I had no idea what to do. (Participant 22)A causal condition is one that induces a particular phenomenon . In thisBecause we are not ICU (intensive care unit) nurses, we didn’t know how to prepare when we heard that a CV  catheter should be inserted. We didn’t even know what Prolene and silk were. I am a charge nurse and yet I did not know how to cope with such a situation, like acting nurses. I didn’t know how to keep a nursing record in the current situation and I didn’t even know what nursing instructions I should give. It was very hard and so I cried a few times during work hours. Every day I was afraid of work. (Participant 18)Central phenomena comprise participants’ behaviors, statements, experiences, or repeated patterns in response to a problem or situation that occurred due to the impact of the causal condition . The cenDifficulties in the workplaceA contextual condition is a collection of concrete temporal relationships or situations influencing the central phenomenon or issue . In thisWorking with goggles, a mask, and a face shield on, I sweat so much. Sweat gets in my eyes and the visual fields through the goggle lenses are whitish. In that condition, I have to change patients’ diapers and positions. If it goes over the maximum of 2 h, I feel dizzy and have a hard time breathing. (Participant 11)The subcategories of “difficulties in the workplace” were “poor work environment”, “uncertainty of manual and guidelines”, “patient’s severity”, and “insufficient and unfair compensation”. Although the participants received regular training, they were not used to performing bedside nursing activities while wearing protective gear. Thus, it was cumbersome for them to put on and remove PPE. Further, their goggles would become foggy, obstructing their vision if worn for long periods. After performing nursing care in PPE for a long time, participants experienced hypoxia, dizziness, and difficulty breathing. If they gave an intravascular injection or performed other delicate nursing activities while wearing multiple layers of gloves, they had to work much slower than usual, expending great amounts of physical energy. There was no guarantee of days off, and the work schedule could be revised without notice, which meant that they had to be on constant standby for emergency calls. Additionally, because the nurses worked near patients in PPE, they often had to perform duties ordinarily performed by physicians, laboratory technicians, nurses’ assistants, and cleaners:We have the KCDC guidelines for infection control, but the guidelines do not contain details. So, ultimately, the definitions for the concepts of “contamination” and “clean” are determined by each hospital in accordance with their situation, and we act accordingly. So, we were very confused on top of being busy at work. In addition, every day, I go to work and find that the job manual has changed. For example, the instructions for doing certain nursing tasks for inpatients would change on a daily basis. (Participant 3)The Korea Centers for Disease Control and Prevention (KCDC) released infection control guidelines, but they do not include all the details relevant to the COVID-19 pandemic and thus could not be directly applied to bedside care, which caused additional confusion. Generally, each healthcare institution has its own guidelines for infection control. However, those guidelines did not provide guidance for all possible scenarios, adding to the confusion. Furthermore, the guidance for patient nursing practices changed frequently, and new hospital guidelines for infection control were sometimes communicated to the nurses incorrectly:The nurses experienced extreme fear and frustration when a COVID-19 patient’s condition worsened. When a patient died suddenly, the nurses experienced increased psychological suffering, which increased their feelings of guilt.The bi-weekly wage of those dispatched by the city government was almost the same as what we get by working for a month. They ask for too much dedication from us. We don’t even get a risk payment. (Participant 8)What we needed so urgently was not a high number of nurses working unconditionally. We needed nurses with ICU experience. But the supplemental nurses were those on a break from their nursing career who could not handle even IV lines well. Ultimately, our job load remained the same. (Participant 17)Just because we had to wear level D and PPE, I sometimes did physicians’ jobs like Ambu-bag bagging and arterial puncture for them. If an accident happens while we do their jobs, however, who will protect us? And yet, we had to do as we were told. (Participant 9)Disruption in daily lifeThe government announced compensation programs for COVID-19 healthcare professionals. However, the programs did not adequately reflect the level of difficulty in healthcare practice, and compensation was paid either to those at screening centers or only to healthcare professionals who were dispatched with the support of a city government or the central government. The programs created a feeling of relative deprivation among nurses working as COVID-19 healthcare professionals in hospitals. In addition, many of the supplemental nurses who had been hired with governmental support were returning to bedside nursing after taking a break from their nursing career, so they required infection control training, increasing the nurses’ job load rather than helping alleviate it. The nurses required in practice were those with professional knowledge and skills who could care for severe patients. The lack of a workforce with these skills was a serious problem:I could not go to my house. I got a place for myself and lived away from my family. My grandmother who cares for my children is also at high risk, vulnerable to infection, and my children are still young. So, my family told me not to come home. Since my friends, whom I often met, found out that I care for COVID-19 patients, we contacted one another only through SNS . (Participant 15)The subcategories of “disruption in daily life” were “isolation from family and friends”, “uncomfortable stares from people around them”, and “meticulously observing social distancing”. As healthcare professionals, the participants practiced social distancing in their daily lives more faithfully than anyone else in order to protect patients. In addition, some participants who had family members with a chronic illness moved out of their homes to stay away from them. Furthermore, participants stopped meeting friends in person and limited their activities to going back and forth between the hospital and their accommodations. Having restricted outdoor activities involving large gatherings, they stopped participating in hobbies that had previously helped them destress. Affected by these contextual conditions, nurses experienced the central phenomena:Ability to copeAn intervening condition is one that deintensifies or induces a change in a phenomenon being experienced; it is a factor that facilitates or inhibits action/interaction . The intIn the beginning, it was tough to care for COVID-19 patients because I didn’t know how to care for them, but my past 20 years of experience could not be ignored. It was always my role to control the COVID-19 patients who were really fussy. (Participant 16)CamaraderieThe subcategories of “ability to cope” were “application of past experiences of caring for severe patients and MERS patients”, “wits in an emergency situation”, and “learning how to care for severe patients”. Nurses who had experience handling ventilators, CRRT, and ECHMO  adapted to the new tasks faster than the others. Experience providing bedside care in PPE during the MERS outbreak was of great help in the new situation. Even amidst an emergency situation that no one had experienced before, proficient nurses were able to cope very quickly. Managing the anxieties of sensitive patients infected by COVID-19 was a burdensome job for nurses, but those patients were no different from difficult patients in general for experienced nurses who had seen a wide variety of patients:If, in the patient’s room, a COVID-19 patient undergoes bronchoscopy or we prepare for CRRT, we have so many things to do. If I asked a colleague to do a nursing task and had to check whether or not the task was properly done, how could I do my job? I can only do my job well because the nurse competently did the task. (Participant 21)Support systemThe subcategories of “camaraderie” were “colleagues whom I can rely on for my safety”, “colleagues who shared tough times with me”, and “colleagues who complete their share of work”. Participants sustained themselves through camaraderie, even though they had difficulties adapting to providing care for COVID-19 patients. This was not a feeling they shared simply because they worked together. Participants meticulously followed the infection prevention measures because they believed that an infection in one of their colleagues would put them all at risk. Participants depended on their colleagues and tried to create a safe work environment. Though it was grueling to cope with emergency situations while wearing protective gear, they could sustain themselves with the thought that they were not alone because their colleagues were with them. In addition, they gained the strength to carry on because each of them was performing their given role to the full:My friends sent gifts and encouraging messages through SNS, thanking us for our sacrifices and dedication. (Participant 13)The subcategories of “support system” were “active support from nurse managers”, “family members’ interest and understanding”, “the encouragement of the people around them”, and “availability of childcare centers for work and childrearing”. When participants watched the nurse manager echo the guidance offered and revamp and coordinate a variety of issues to improve the job environment, they felt comforted knowing that everyone was hard at work. Further, participants were greatly inspired by the knowledge that their family was sincerely concerned about them and that they understood what they were doing at work. They were also grateful when friends and others recognized their hard work and dedication:It was really tough to accept that no institution can provide childcare in this situation; meanwhile, they are concerned about the serious problem of the country’s low birth rate. Yet, no one can care for my children. I asked my 7-year-old to babysit my 4-year-old so I could go to work. Although my husband came home in the morning after working a night shift, I was scared that something might happen during the few intervening hours. (Participant 15)Some participants were raising young children and had difficulty making childcare arrangements when they had to go to work. Childcare centers might be closed, and friends or family might not be able to babysit if a close contact of a confirmed case had been identified. Some childcare centers to which participants had previously sent their children refused to accept them because their mother’s profession elevated the child’s risk of infection. In some cases, even participants’ parents refused to help with childcare because they were afraid of infection. Additionally, since schools were no longer holding face-to-face classes, participants were also responsible for their children’s education:Period of confusion: Dashing firstAn action and interaction strategy is a strategy or routine/habitual behavior used to cope with a problematic situation; it describes with whom and how those facing a problem interact in the context of the challenging phenomenon . ParticiThe confusion period is the stage in which nurses caring for COVID-19 patients went through trial and error when they had no idea what to do with the new infectious disease. During this time, the participants were unable to predict their daily tasks, so they used an interaction strategy called “dashing first”. Each time the nurses went to work, they had to become familiar with the changed work protocols, and they had to quickly perform admission and discharge care for patients in the evening. In this stage, to increase the nurses’ ability to adapt at work, three shifts often suddenly changed to two, and nurses who were on vacation would suddenly need to report to work due to understaffing. Whenever such a situation occurred, it was accepted as an unavoidable problem, and, once it became reality, it became a process of learning to work passively.The night shift starts at 10:30. I got a phone call from the ward around 10 to come in and work. That was supposed to be my day off, so I was getting ready to go to bed. But as soon as I got the phone call, I got ready and went to work. This has happened often. (Participant 4)Period of burnout: Enduring on the very last of my strengthThe subcategories of “dashing first” were “handling the situation at hand first”, “accepting a life with no break from work”, “always standing by for a sudden call to work”, and “asking other departments for help”. It was not easy for participants to adapt to the daily-changing job manual, but they started focusing on caring for patients. They often exchanged opinions with colleagues after work through group SNS accounts, and were thus constantly performing their jobs at home. As they continued to work overtime, the work schedule was changed to a two-shift pattern to increase efficiency in patient care. However, when that work framework was established and the system had stabilized, it changed again, this time to a three-shift pattern. Nonetheless, there was always a shortage of proficient nurses to care for severe patients. Participants were called into work without notice due to insufficient staffing. They requested that other departments, like the ICU, help by dispatching their personnel because they were unfamiliar with the equipment needed to care for severe patients:Period of leaping forward: Growing stronger to get back upThe burnout period is a stage that appears over time after a period of confusion has been passed through. At this stage, nurses used the interaction strategy of “enduring on the very last of my strength”. The subcategories of “enduring on the very last of my strength” were “repetition of work and sleep” and “waiting to take days off”. In the burnout period, the nurses were so physically and psychologically exhausted that they had no energy to do anything. They endured the time by repeating a pattern of sleeping immediately after work and going to work immediately after waking, while having no time for hobbies or a personal life; when they worked, they waited only for days off. Some nurses made a more rapid transition from burnout to leaping forward than others depending on their coping ability, camaraderie, and support system.The period of leaping forward is a step towards using aggressive coping strategies in clinical conditions, wherein participants showed an interaction strategy of “growing stronger to get back up”. In this stage, nurses gained specialized nursing knowledge about new infection management and critical care, or sought effective nursing practice strategies by reflecting on emergency situations. In addition, the participants not only promoted their inner strength at this stage but also encouraged and supported their colleagues, recharging their power to rise together.I was so exhausted that I wanted to give up everything. But I improved my physical strength by exercising. Because I could not go to any place where there were many people, to protect myself from getting infected with COVID-19, I began to do exercises I could do alone. I utilized home training as much as I could by watching YouTube videos. (Participant 19)Period of stabilization: Dreaming about the end of the COVID-19 pandemicThe subcategories of “growing stronger to get back up” were “accepting the self as imperfect”, “acquiring professional nursing knowledge”, “reflecting on the situation”, “blocking out unnecessary sources of emotion”, “recharging energy”, “sympathizing with colleagues”, and “considering colleagues’ perspectives first”. Although participants were fatigued as they experienced trials and errors in the persistent COVID-19 situation, they used various interaction strategies to grow stronger and continue their work. They let go of their self-image as the proficient nurses they had been in the past and accepted that they were now novices who were unfamiliar with the nursing care required by COVID-19 patients. They began addressing their shortcomings. To acquire the professional nursing knowledge needed to care for severe patients, they participated in hospital training for intensive care nursing. After experiencing an emergency situation, they re-examined the situation and contemplated problem-solving approaches. To minimize their emotions while caring for COVID-19 patients, they tried to view problems objectively. Since they were physically exhausted by the time they were used to the job, they began to exercise again to recharge their energy stores. Further, in sharing their frustrations and talking with colleagues, participants enjoyed being recognized for their efforts to do their best in a demanding situation and were able to comfort themselves. They performed small, considerate acts for their colleagues, such as offering a glass of water to a colleague who was tired after wearing PPE for more than two hours and recording a video demonstrating how to operate a particular ICU machine for the benefit of colleagues who were not yet proficient:The stabilization period occurred when the nurses were able to proficiently perform nursing tasks with which they were unfamiliar at the beginning of the pandemic. This stage involved skillfully performing new infection management and critical care services with which they were not familiar when they began nursing patients with COVID-19. In this stage, the nurses showed an interactive strategy of “dreaming about the end of the COVID-19 pandemic” in a stable way, working with little hope that this situation would ever end. The nurses comforted each other by talking about dreams they had not yet realized due to COVID-19 and about how the pandemic would end once a vaccine had created a collective immunity.Won’t the COVID-19 situation be over some time down the road? Without hope, how can we live today? (Participant 16)The subcategories of “dreaming about the end of the COVID-19 pandemic” were “holding on to hope”, “imagining going on a trip”, and “making a bucket list”. Although the end of COVID-19 was not yet in sight, participants withstood daily life by not losing hope that the pandemic would end. Participants said that, had they not held onto even the vague hope that the pandemic would end, they would not have had the strength to live each day. Many participants reminisced about the trips they had taken and spoke about their bucket lists of travel destinations they planned to visit when the situation improved. Participants dreamt about the future by creating other bucket lists, stating that they remembered the things they could not do because they were busy caring for COVID-19 patients:Growth as an expert nurseThe results derived through action/inaction were “growth as an expert nurse” and “changing career path”.Now, I am familiar with the job to some extent, due to the manual we created. I am also used to wearing level D and PPE. When I receive a CRRT or ECHMO order, I don’t get scared; instead, I can handle it with proficiency. (Participant 1)In this situation, I think our job of watching over patients is really meaningful. I also believe that our job has professionalism. As I overcame the uphill battle, I realized that many healthcare professionals rely on nurses’ professionalism. (Participant 7)Changing career pathThe subcategories of “growth as an expert nurse” were “job stabilization”, “establishment of a viewpoint on nursing professionalism”, and “heightened awareness of ethical responsibility”. Over time, participants felt that they were growing, as they systematized and familiarized the tasks involved in caring for COVID-19 patients. They found the meaning of nursing in the familiar work, recognized the professionalism of nursing, and took pride in being nurses. In addition, participants pledged that, as nurses caring for patients on the frontline of the COVID-19 pandemic, they would make sure to fulfill their ethical responsibility:I am going to quit working at the hospital once the pandemic is over. I want to have time to look after myself. There is talk about compensation at the government level, but I don’t expect anything. I sacrificed my life to care for patients, but we got nothing back. (Participant 3)The subcategories of “changing career path” were “a decision to change jobs” and “preparing for another job.” Some nurses decided to leave bedside nursing although they had become familiar with the nursing tasks. Reflecting on the past, during which they tirelessly worked caring for patients, they decided to leave a situation in which they were pressured, without any compensation, to make sacrifices and dedicate themselves to a national disaster only because they were nurses. They wanted to make a change in their lives. Some nurses tried to find another job and studied for another field:This study was conducted to explore how nurses adapted in order to care for COVID-19 patients during the COVID-19 pandemic using a grounded theory approach. The aim was to develop a substantive theory and provide the basic data needed to develop intervention programs to support nurses caring for COVID-19 patients.The study found that “growing as a proficient nurse alongside comrades on the COVID-19 frontline” was the core category. A previous study that analyzed nurses’ experience of caring for COVID-19 patients using a phenomenological methodology  also fouThe study found that the causal condition was “the COVID-19 frontline toward which nurses were suddenly pushed.” A phenomenological study that examined the experiences of nurses caring for COVID-19 patients  similarlThe study found that “complex emotions” constituted the central phenomena. Such phenomena were also found in nurses caring for MERS patients ,11,22. SThe contextual conditions in the study were “difficulties in the workplace” and “disruption in daily life.” These problems were also identified during the MERS outbreak ,11,22 anWhile adapting in order to care for COVID-19 patients, participants went through periods of “confusion”, “burnout”, “leaping forward”, and “stabilization”, and used “dashing in headfirst”, “enduring on the very last of my strength”, “growing stronger to get back up”, and “dreaming about the end of the COVID-19 pandemic” as interaction strategies. A previous study on workplace learning among nurses reported a similar adaptation process . Nurses The study’s intervening conditions were “ability to cope”, “camaraderie”, and “support system”. If these intervening conditions are insufficient, nurses will remain in the confusion and burnout periods for a long time. Nurses can move through the adaptation process stages quickly if their ability to cope, camaraderie, and support system levels are high enough. The participants’ past experiences of caring for emergency and severely ill patients over the years were integrated into their coping abilities, impacting their adaptation to the COVID-19 situation. When nurses face a new situation, their patient nursing experiences are integrated with their training, triggering professional growth . To faciConsistent with the intervening conditions derived in this study, a previous study identified “camaraderie”, “patience”, and “encouragement” as factors that helped nurses endure the MERS outbreak, which was a similarly challenging situation . FurtherHowever, previous research did not find that the lack of childcare centers and childrearing resources was a support system problem because the MERS outbreak lasted for barely a year, while the COVID-19 pandemic began in March 2020 and was still ongoing in March 2021. The situation examined in this study was more challenging for participants, who had to work while caring for their children because childcare centers had closed. Previous studies found that stress levels amidst the COVID-19 pandemic were higher among married nurses than unmarried nurses due to the former’s increased fatigue and feelings of guilt while attempting to balance work and childcare ,31. The Similar to the experiences of nurses caring for MERS patients ,11,22, tThe COVID-19 pandemic has lasted longer than the MERS outbreak, and some of the nurses examined in this study decided to leave bedside nursing or were preparing to change jobs. Given the severe nursing shortage, measures to support nurses who plan to leave the bedside or change jobs are urgently needed. A previous study on nurse turnover  reportedThis study has several limitations. First, in Korea, over 20,000 men have been licensed as nurses, comprising approximately 5% of the country’s nursing profession , but theThis study was conducted to understand nurses’ adaptation processes in caring for COVID-19 patients. A grounded theory approach was taken in order to provide the basic data needed to develop intervention programs designed to support nurses caring for COVID-19 patients.The results of this study show that nurses transitioned from the burnout to the leaping forward stages more rapidly if they had greater coping ability, camaraderie, and support system levels. Therefore, supporting nurses in their systematic coping with emerging infectious diseases requires the regular provision of basic education regarding the care for patients with these diseases and the creation of educational programs that can train nurses specialized in the field of infectious disease. This study also recommends creating a support system for both work and childrearing, the importance of which is shown in the intervening conditions. The evidence offered through this study’s investigation of nurses’ adaptation processes in caring for COVID-19 patients can assist in developing strategies for helping nurses adapt in their jobs and in preventing nurse burnout when another emerging infectious disease occurs. The study’s findings can also be used to establish programs that can prevent the turnover of expert nurses with experience in caring for COVID-19 patients.