Martin Müller, RGN, Dipl. Nurs. Mngt1,2, Eva Grill, DrPH, PhD1,2, Marita Stier-Jarmer, PhD1,2, Ralf Strobl, Dipl. Stat1,2, Christoph Gutenbrunner, MD3, Veronika Fialka-Moser, MD4 and
Gerold Stucki, MD, MS2,5,6

From the 1Institute for Health and Rehabilitation Sciences (IHRS), Ludwig-Maximilians-Universität München, Munich, Germany, 2ICF Research Branch of WHO Collaborating Centre for the Family of International Classifications in
German, Nottwil, Switzerland, 4Department of Physical Medicine andRehabilitation, University Hospital Vienna, Vienna, Austria, 5Swiss Paraplegic Research, Nottwil and 6Seminar of Health Sciences and Health Policy, University of Lucerne, Switzerland

OBJECTIVE: To examine the relevance and completeness of the comprehensive International Classification of Functioning, Disability and Health (ICF) Core Sets for patients with rehabilitation needs in acute hospital care.

DESIGN: Multi-centre cohort study.

Patients: A total of 391 patients (50.1% female, mean age 63.4 years) from 4 university hospitals in Austria, Germany and Switzerland and one Austrian general hospital.

METHODS: Data on functioning were collected using the respective comprehensive acute ICF Core Sets. Data were extracted from patients’ medical record sheets and interviews with health professionals and patients.

RESULTS: Most of the categories of the comprehensive ICF Core Sets describing impairments, limitations or restrictions occurred in a considerable proportion of the study population. The most outstanding limitations and restrictions of the patients were problems with sleep and blood vessel functions, walking and moving and self-care. Thirty-eight aspects of functioning not previously covered by the comprehensive ICF Core Sets were ranked as relevant.

CONCLUSION: Categories of the comprehensive ICF Core Sets for the acute hospital situation were confirmed. Some additional categories not covered by the Set in its present version emerged from the interviews, and should be considered for inclusion in a finalized version.

Key words: ICF; cohort study; intensive care; outcome assessment; classification.

J Rehabil Med 2011; 43: 92–101

Correspondence address: Eva Grill, Institute for Health and Rehabilitation Sciences, Ludwig-Maximilians-Universität München, DE-81377 Munich, Germany. E-mail eva.grill@med.uni-muenchen.de

Submitted May 25, 2010; accepted August 30, 2010

Introduction

Despite the rapid progress in survival after an acute injury or disease, which has been afforded by modern medicine, long-term outcomes can be less favourable. Typically, the risk for subsequent disability is particularly elevated in critically ill patients, in patients with complications or long-term intensive care stays, in persons with disabilities or pre-existing chronic conditions, and in older patients. Any of these circumstances may result in prolonged immobilization, which can give rise to contractures ultimately restricting the patients’ ability for self-care (1), or otherwise engender a wide range of adverse neuropsychological effects (2) specifically due to immobilization.

It is increasingly recognized that an appropriate and early start to rehabilitation contributes importantly to the maintenance of functioning, prevention of disability, and optimal recovery of patients in the acute situation (3–4). Thus, the needs for rehabilitative intervention of those patients in acute hospital care with an increased risk for considerable loss of functioning should be identified as early as possible (5). To this end, healthcare professionals in the acute hospital should be able to make a brief assessment of their patients’ functioning, and set in motion timely strategies for meeting their subsequent rehabilitation needs. The acute care providers have first to identify especially vulnerable patients, such as the aged, or those with co-morbidity. In order to communicate their patients’ particular needs with rehabilitation professionals, there must be a standard system of describing human functioning and rating disability.

The International Classification of Functioning, Disability and Health (ICF) (6), a part of the international family of classifications of the World Health Organization, was established as just such an approach to standardizing the assessment of functioning of individuals and populations. The ICF endeavours to organize all domains of functioning and their contextual factors that are encountered in human life, and may thus arguably constitute the prototypical framework for all medicine. Comprising over 1400 categories, the ICF must nonetheless be adapted to the perspectives and needs of different users. This task is the primary motivation behind the ICF Core Set project, which aims to extract a selection of ICF categories from the entire classification that are relevant for specific health conditions or care situations. This on-going selection of the comprehensive ICF Core Sets shall define common standards for what should properly be measured and reported.

In general, the ICF Core Set project defines on an empirical basis a category as relevant when it describes a problem that is frequently encountered in typical patients, measured as an endpoint in clinical trials, or was otherwise identified as being relevant following discussion among health professionals. The resultant information is then summarized and implemented as part of a formalized consensus process involving expert health professionals (7). Comprehensive ICF Core Sets for the acute hospital have already been developed for patients with neurological, cardiopulmonary and musculoskeletal conditions (8–10).

Comprehensive ICF Core Sets can be used for the assessment of problems and needs in the acute situation, as well as for the estimation of prognosis and rehabilitation potential (8). Likewise, they can be used to coordinate rehabilitation interventions, e.g. at the intensive care unit. Finally, the Sets can serve as a list of potential candidate categories for creating new measures tailored to the needs of the respective user.

In order to validate the comprehensive ICF Core Sets designed for use in particular contexts, one must possess an adequate understanding of the methodological framework used for creating measures. For example, the Outcome Measures in Rheumatology (OMERACT) project identifies 3 different properties relevant to the applicability of measures, namely truth, discrimination and feasibility (9). The first two of these criteria, truth and discrimination, can be applied to test the validity of the comprehensive sets. The criterion truth refers to the question of what should be measured. As noted above, the process for generating the comprehensive ICF Core Set assured that all the relevant aspects of functioning were included, but the empirical validation of the choice of categories remains to be completed. The criterion discrimination refers to the ability of a measure to discriminate between different states of functioning or medical conditions. A discriminating measure must distinguish between different patient groups in a cross-sectional manner, and assess change in functioning over time.

The objective of this study was to examine the relevance and completeness of the comprehensive ICF Core Sets for patients receiving rehabilitation interventions in the acute care setting. Specifically, we wanted to examine which aspects of functioning included in the comprehensive acute ICF Core Set:

• were frequent at admission to and at discharge from acute care,

• changed during hospital stay, and

• also to identify new relevant aspects for inclusion in the revised ICF Core Set.

Methods

Study design

A full description of the methods used in this study has been reported elsewhere (10). In brief, study design was a prospective multi-centre cohort study conducted from May 2005 to August 2008. The study population was recruited from 4 university hospitals in Austria, Germany and Switzerland and one Austrian general hospital; approximately 57% of the patients were recruited from the Austrian centres, 24% from the German centres, and 19% from the Swiss centre. Patients were eligible if they were at least 18 years of age and received team integrated multiprofessional rehabilitation interventions for acute musculoskeletal, neurological, or cardiopulmonary injury or disease. As such, rehabilitation interventions could be provided either at a dedicated rehabilitation ward situated in the acute hospital or by mobile rehabilitation teams caring for patients on medical or surgical wards. Written informed consent was obtained from the patients or from the patient’s caregiver in cases where the patient was unable to make an informed decision. Approval was obtained from institutional ethics committees from all involved institutions prior to starting the study.

Measures

For the assessment of functioning, we used the 3 comprehensive ICF Core Sets for patients in the acute hospital situation, which were earlier developed to address the specific situations of patients with neurological, musculoskeletal, or cardiopulmonary conditions (11–13). For all patients, impairments in categories of the component Body Structures were graded as present or absent. Limitations or restrictions in categories of the components Body Functions and Activities and Participation were graded as “none”, “slight/moderate/severe” or “complete” limitation or restriction. The categories of the component Environmental Factors were graded either as facilitator or barrier, or both facilitator and barrier, or neither facilitator nor barrier.

We elected to report only those impairments, limitations and restrictions directly associated with the conditions causing the need for rehabilitation. The interviewers obtained information from the ward staff in charge about which of the impairments, limitations or restrictions resulted from the referring condition or principal diagnosis, and which occurred as a result of a specific co-morbidity. In order to validate the completeness of the comprehensive ICF Core Sets, the interviewers were furthermore asked to identify any aspects of functioning relevant to the patient, but not currently covered by the comprehensive ICF Core Sets. Additionally, socio-demographic (sex, age, education, living and occupation situation) and condition-specific data (underlying diagnosis, time until rehabilitation, number of co-morbidities and length of stay) were recorded.

Data collection procedures

Data were collected primarily from patients’ medical record sheets, health professionals in charge of the patients, and from patients’ interviews. Interviewers collecting data had been trained in the application and principles of the ICF, and provided with a manual. All interviewers were health professionals (physicians, medical students in clinical training, physical therapists, or nurses). During data collection interviewers obtained support and information from the ward staff in charge. Ongoing supervision of the interviewers was ensured by periodic telephone calls.

Data collection took place within the first 24 h after admission to the hospital (baseline) and within the last 36 h before discharge or, if length of stay was longer than 6 weeks, at 6 weeks after admission (end-point). ICF categories from the component Environmental Factors were assessed only at admission, since we did not expect any change in these categories during hospital stay.

Statistical analysis

For the categories of the ICF components Body Functions, Body Structures and Activities and Participation we calculated the absolute and relative frequencies (prevalences) of impairment, limitation or restriction at baseline and end-point. For the categories of the ICF component Environmental Factors, we calculated the absolute and relative frequencies (prevalences) of persons who regarded a specific category as constituting either a barrier or facilitator. Relative frequencies of persons for whom the ICF category changed during the study period were calculated, along with their 95% confidence intervals (CI). Frequencies were calculated based on all available participants; change was calculated based on participants with data at baseline and at end-point. A difference between baseline and endpoint was considered as change if the percentage of change was different from null and the confidence interval did not include the null.

Aspects of functioning not covered by the comprehensive ICF Core Sets but identified as relevant were extracted and translated into the best corresponding ICF category. Absolute and relative frequencies of occurrence of those ICF categories were reported; any such category with prevalence below 5% was considered as not relevant.

Results

Sociodemographics

In total, 391 patients were included. Mean age at admission was 63.4 years (median 65.6; standard deviation (SD) 18.2 years). Mean length of stay was 14.9 days (median 10; SD 13.7). Fifty percent of the patients were female. Ninety-one had a neurological, 109 a cardiopulmonary and 191 a musculoskeletal condition. Twenty patients (5%; 3 neurological, 3 cardiopulmonary, 14 musculoskeletal) were lost to follow-up because of unplanned discharge from hospital or death. The most frequent admission diagnoses classified according ICD-10 in patients with neurological conditions were “cerebrovascular diseases” (including cerebral haemorrhages and infarctions) (n = 46; 50.5%), and “diseases of the nervous systems”, including transient cerebral ischaemic attack, hemi- or tetraplegia (n = 18; 19.8%). The most frequent admission diagnoses in patients with cardiopulmonary conditions were “Other forms of heart disease” (including cardiomyopathy, myocarditis, and heart failure) (n = 30; 27.5%) and “Ischaemic heart diseases” (including myocardial infarction) (n = 22; 20.2%). The most frequent admission diagnoses in patients with musculoskeletal conditions were “Other dorsopathies” (including disc disorders and low back pain) (n = 46; 24.1%) and “Arthropathies” (including arthritis and arthrosis) (n = 24; 12.6%). For further socio-demographic and condition-related variables see Table I.

Functioning and disability

Tables II–IV give the prevalence of impairment or restriction both at admission and discharge as well as the corresponding 95% CI for the frequency of change in impairment or restriction, for each category of underlying condition.

Of the categories of the components Body Functions and Structures and Activities and Participation from the comprehensive ICF Core Sets, 55% were impaired or restricted for patients with neurological conditions in at least one-third of the patients, vs 71% from the cardiopulmonary patient group, and 57% from the musculoskeletal patient group.

Functioning and disability in patients with neurological conditions

The frequency of impairments or restrictions in patients with neurological conditions ranged from 2% to 86% (mean 38%) at admission and from 1% to 82% (mean 26%) at discharge. There were 3 categories with prevalence below 5% at admission or discharge: Heart functions (b410), General metabolic functions (b540), Structure of respiratory system (s430), and Hearing functions (b230).

The Body Functions and Body Structures most frequently impaired both at admission and discharge were Muscle power functions (b730) (81% at admission/72% at discharge), Control of voluntary movement functions (b760) (69%/53%), Blood vessel functions (b415) (60%/52%) Muscle tone functions (b735) (60%/51%), Structure of brain (s110) (86%/82%), and Structure of cardiovascular system (s410) (72%/61%).

The ICF categories from the component Activities and Participation (A&P) most frequently limited at admission were Caring for body parts (d520) (76%), Moving around using equipment (d465) (75%) and Hand and arm use (d445) (73%), the most frequently limited at discharge were Fine hand use (d440) (51%), Hand and arm use (d445) (49%) and Moving around using equipment (d465) (45%).

The percentage of patients reporting an improvement in functioning at discharge ranged from 0% to 44% for the different ICF categories. The most frequent improvements were observed in A&P categories Moving around using equipment (d465) (44%), Toileting (d530) (42%), Changing basic body position (d410) (41%), and Caring for body parts (d520) (41%). The Body Functions which improved most frequently were Blood vessel functions (b415) (38%), Energy and drive functions (b130) (30%), and Control of voluntary movement functions (b760) (28%). The most frequent improvement in Body Structures was found in the Structure of cardiovascular system (s410) (13%).

The percentage of patients who reported deterioration in any of the different ICF categories ranged from 0% to 11%, which was observed in both Attention functions (b140) and Stability of joint functions (b715).

Functioning and disability in patients with cardiopulmonary conditions

The frequency of impairments or restrictions in patients with cardiopulmonary conditions ranged from 7% to 98% (mean 46%) at admission and from 4% to 87% (mean 33%) at discharge. There was no category with prevalence below 5% at admission.

Body function categories had the highest prevalence of impairment both at admission and at discharge. As expected, impairments in Functions of the respiratory system (b440–b449) and Additional functions and sensations of the cardiovascular and respiratory systems (b450–b499) were most frequent in this patient group.

The Body Functions most frequently impaired at admission were Exercise tolerance functions (b455) (98%), Sensations associated with cardiovascular and respiratory function (b460) (83%), and Respiration functions (b440) (70%), the most frequently impaired at discharge were Exercise tolerance functions (b455) (87%), Sensations associated with cardiovascular and respiratory function (b460) (64%), and Heart functions (b410) (59%).

The Body Structures most frequently impaired both at admission and at discharge were Structure of cardiovascular system (s410) (72% at admission/69% at discharge), and Structure of respiratory system (s430) (55%/46%).

The ICF categories from the component A&P most frequently limited at admission were Walking (d450) (61%), Washing oneself (d510) (58%), Caring for body parts (d520) (56%), and Dressing (d540) (56%), the most frequently limited at discharge were Walking (d450) (36%), Handling stress and other psychological demands (d240) (35%), and Washing oneself (d510) (30%).

The percentage of patients reporting an improvement in functioning at discharge ranged from 2% to 35% for the different ICF categories. The most frequent improvements were observed in A&P categories Toileting (d530) (35%), Dressing (d410) (33%), Walking (d450) (32%), and Caring for body parts (d520) (32%). The Body Functions which improved most frequently were Exercise tolerance functions (b455) (33%), Respiration functions (b130) (25%), and Additional respiratory functions (b450) (25%). However, impairments in Exercise tolerance functions (b455) were highly frequent also at discharge. The most frequent improvement in Body Structures was found in the Structure of respiratory system (s410) (10%).

For the different ICF categories, the percentage of patients reporting a deterioration of functioning at discharge ranged from 0% to 8%, which was observed in 5 categories: Blood pressure functions (b420), Additional respiratory functions (b450), Ingestion functions (b510), Changing basic body position (d410), and Maintaining a body position (d415).

Functioning and disability in patients with musculoskeletal conditions

The frequency of impairments or restrictions in patients with musculoskeletal conditions ranged from 3% to 95% (mean 46%) at admission and from 0% to 85% (mean 31%) at discharge. There were two categories with prevalence below 5% at admission Consciousness functions (b110) and Experience of self and time functions (b180).

The Body Functions and Body Structures most frequently impaired both at admission and at discharge were Muscle power functions (b730) (94% at admission/85% at discharge), Mobility of joint functions (b710) (92%/84%), Sensation of pain (b280) (91%/66%), Structure of areas of skin (s810) (64%/59%), and Structure of lower extremity (s750) (53%/55%).

The ICF categories from the component A&P most frequently limited at admission were Changing basic body position (d410) (95%), Transferring oneself (d420) (90%), and Walking (d450) (88%), the most frequently limited at discharge were Walking (d450) (71%), Changing basic body position (d410) (60%), and Caring for body parts (d520) (49%).

The percentage of patients reporting an improvement in functioning at discharge ranged from 1% to 64% for the different ICF categories. The most frequent improvements were observed in A&P categories Transferring oneself (d420) (64%), Changing basic body position (d410) (58%), Maintaining a body position (d415) (55%), and Toileting (d530) (55%). The Body Functions which improved most frequently were Sensation of pain (b280) (33%), Mobility of joint functions (b710) (31%), and Stability of joint functions (b715) (31%). The most frequent improvement in Body Structures was found in the Structure of cardiovascular system (s410) (12%).

For the different ICF categories, the percentage of patients reporting a deterioration of functioning at discharge ranged from 0% to 5%, which was seen for two categories: Emotional functions (b152) and Muscle tone functions (b735).

Common aspects of functioning and disability in the 3 patient groups

A comparison of the 3 condition groups showed that there were several categories with highly frequent impairment (> 50% of patients) irrespective of the category at admission. These frequently occurring impairments were Sleep functions (b134) (57–66%), Blood vessel functions (b415) (55–60%), Walking and moving categories (Walking (d450) in patients with cardiopulmonary and musculoskeletal conditions and Moving around using equipment (d465) in patients with neurological conditions) (61–88%), and some of the Self-care categories (d510–d540) (53–81%). In patients with neurological or musculoskeletal conditions at admission, the most frequent impairments and limitations were in Muscle Functions (b730–b735) (55–94%) and Changing and maintaining body positions (d410–d420) (61–95%).

Contextual factors

Table V gives an overview of the prevalence of categories from the component Environmental Factors, which served as facilitators or presented barriers, stratified by condition.

Environmental factors in patients with neurological conditions

The frequency of facilitators in patients with neurological conditions ranged from 16% to 100% (mean 75%), whereas the frequency of barriers ranged from 1% to 42% (mean 11%). There were no facilitators with prevalence below 5%, but 7 barriers had prevalence below 5%. The most frequent facilitators were Individual attitudes of health professionals (e450) (100%), Health professionals (e355) (97%), Health services, systems and policies (e580) (96%), and Immediate family (e310) (93%). The most frequent barriers were Sound (e250) (42%), Social norms, practices and ideologies (e465) (23%), and Products and technology for personal use in daily living (e115) (20%).

Environmental factors in patients with cardiopulmonary conditions

The frequency of facilitators in patients with cardiopulmonary conditions ranged from 22% to 98% (mean 77%); there were no categories serving as facilitators in less than 5% of the patients. The most frequent barriers, which ranged from 2% to 33% (mean 11%), were Air quality (e260) (33%), Sound (e250) (30%), Products or substances for personal consumption (e110) (16%), and Products and technology for personal use in daily living (e115) (15%); 5 categories were a barrier for less than 5% of the patients.

Environmental factors in patients with musculoskeletal conditions

The frequency of facilitators in patients with musculoskeletal conditions ranged from 72% to 98% (mean 83%). The most frequent facilitators were Health professionals (e355) (98%), Individual attitudes of health professionals (e450) (94%), and Health services, systems and policies (e580) (92%); there were no categories as facilitators with prevalence below 5%. The frequency of barriers ranged from 1% to 24% (mean 10%). The most frequent barriers were Products or substances for personal consumption (e110) (24%), Products and technology for personal use in daily living (e115) (16%), and Products and technology for personal indoor and outdoor mobility and transportation (e120) (14%); two categories had prevalence as barriers below 5%.

Additional ICF categories

Thirty-eight aspects of functioning not previously covered by the comprehensive acute ICF Core Sets were identified as relevant. However, many of these aspects were only mentioned by one person, and so cannot be considered as representative. Aspects which were mentioned by at least 1% of the participants are presented in Table VI. All of these newly identified aspects could be translated into corresponding ICF categories. Ten aspects referred to categories and chapters of the component Body Functions, 17 to categories and chapters of the component Body Structures, 7 to categories and chapters of the component Activities and Participation and 3 to categories of the component Environmental Factors.

Discussion

The results of the present multi-centre cohort study provide further insight into the course of functioning and health and its related contextual factors in patients with rehabilitation needs in acute hospital care. The results of our study generally confirm the first version of the comprehensive ICF Core Sets for patients in the acute hospital. We could show that a large number of the categories included in the comprehensive ICF Core Sets address relevant aspects of functioning and disability, and detected a few additional candidates for inclusion.

Irrespective of the health condition, there were high prevalences of impairment in Sleep functions (b134) and Blood vessel functions (b415), and also limitations in Walking and moving (d450–d469) and in all categories pertaining to Self-care (d510–d540). Sleep loss, sleep disruption and a disturbed circadian rhythm are reported frequently at acute and intensive care units, and have been attributed to several factors, such as interventions, diagnostic procedures, underlying disease or ambient noise (14–15). Impaired blood vessels functions frequently correspond to venous thromboembolism, which is a life-threatening and frequent complication of surgery, and also arising due to prolonged immobility and the use of central venous catheters (16–17).

Limitations in walking and moving, as well as self-care patterns are to be expected in critically ill patients in acute hospitals, in intensive care or in intermediate care units, such as those in the present study. In general, the frequency of impairments and limitations in these categories reflects the seriousness of the underlying illness or disability (18). The present finding of frequently reported impairments in muscle functions and limitations in changing and maintaining body positions in patients with neurological and musculoskeletal conditions agrees with earlier reports on the need of rehabilitative interventions (18–19).

As expected, ICF categories related to brain and vascular systems were impaired in a high proportion of patients with neurological conditions, both at admission and discharge. The high prevalence of impairments related to perception and cognition is also in line with the literature (19–20).

Problems with General metabolic functions (b540), such as diabetes mellitus, were observed in only a small proportion of patients with neurological conditions, although approximately 50% had a cerebrovascular disease (Table I). This is surprising since diabetes is a risk factor for cerebrovascular diseases and should therefore be highly prevalent in patients with neurological conditions (21–23). Since disability after stroke is significantly higher in patients with diabetes (24), the category metabolic functions should be included in a final version of the comprehensive Set as a parameter to be monitored.

The most frequently observed improvements in patients with neurological conditions were in categories of the component Activities and Participation, namely in Changing basic body position (d410), Moving around using equipment (d465), Toileting (d530), and Caring for body parts (d520), which are all categories from mobility and self-care. These improvements reflect the major goals of rehabilitation and nursing care in the acute situation, which are primarily the ability to attain a sitting and standing position (included in Changing basic body position) and ultimately the obtaining of independent mobility with assistive devices such as wheelchairs, walking frames or crutches, as well as regaining independence in very personal activities such as toileting or brushing of teeth (included in Caring for body parts).

We identified some aspects as tending to deteriorate during hospitalization, namely Attention functions (b140) and Stability of joint functions (b715). Arguably, those functions are likely to be disregarded at the initiation of therapy, when survival and stabilization of vital functions are the main concerns. Additionally, joint problems such as subluxation of the shoulder joint, are common in patients with hemiplegia, and tend to exacerbate with time (25).

In patients with cardiopulmonary conditions, impairments in functions and structures connected with the cardiac and pulmonary system had the highest prevalence both at admission and discharge, especially Exercise tolerance functions (b455) and Sensations associated with cardiovascular and respiratory function (b460) (including dyspnoea and air hunger). Accordingly, limitations in a wide range of physical activities such as Walking (d450) and all self-care issues were reported most frequently in these patients. However, it was precisely these issues which improved most frequently during hospital stay, perhaps reflecting the importance of obtaining independence in daily activities as a major goal in cardiopulmonary rehabilitation. On the other hand, the frequent occurrence of limitations in Handling stress and other psychological demands (d240) underscores the relevance of psychosocial interventions in the early course of cardiopulmonary rehabilitation (26–27).

Improvements in Mobility and Self-care again refer to the typical goals of physical therapy and nursing in the acute hospital. Our observations of decline in ingestion and respiratory functions can be attributed to the effects of prolonged immobilization in some patients. In particular, it is unsurprising that patients with musculoskeletal conditions experienced impairment in functions of muscles, bones and joints, as well as limitations in the corresponding categories of the component A&P, such as Walking (d450), Moving around (d455), and, consequently, Self-care. In the course of their recovery and rehabilitation therapy, the degree of pain, mobility and stability of joints had improved at discharge. The deterioration of emotional functions seen in our study is in line with earlier reports, for example on the occurrence of depression after hip fracture (28–29).

The detection of additional topics not covered by the present version of the comprehensive ICF Core Sets were rather infrequent, with the exception of Protective functions of the skin, which came up in almost two-thirds of the patients with musculoskeletal conditions, Moving around, seen in almost 25% of the patients with musculoskeletal and neurological conditions, and Walking, which was noted in more than 25% of the patients with neurological conditions. Those categories seem intuitively reasonable and fit for inclusion in the revised ICF Core Sets. Indeed, they had initially been excluded during the consensus conferences only because the experts on the acute hospital situation sought to derive parsimonious sets, which were not so comprehensive as to be impractical in the clinical situation.

Even though prevalence of impairment, limitation or restriction was rather low in some of the categories, all of those categories showed change. Since assessing change over time arguably is one of the important properties of an assessment instrument (9), we propose to include categories into the comprehensive ICF Core Sets not only on the basis of frequency, but also conditional on their propensity to change.

Some limitations of our study may restrict the generalizability of the results. The sample included only patients from German-speaking countries with comparable healthcare systems. The collection of data elsewhere in Europe, or in other continents, might well have yielded different results. Therefore, additional validation studies with patients from other countries and cultures should be carried out. Impairments and limitations may also be a direct consequence of the underlying diagnoses encountered in the particular study. We are, however, confident that the current sample of older patients reflected the prototypical spectrum of diagnoses seen in Europe. Nevertheless, the best validation for comprehensive ICF Core Sets is to use them in practice as often as possible, and in many different settings.

In conclusion, the categories of the comprehensive ICF Core Sets for the acute hospital situation were confirmed. Due to their sensitivity to change no categories of the comprehensive ICF Core Sets should be excluded. The categories Moving around (d455) and Walking (d450) have to be included in the final version of the comprehensive ICF Core Set for neurological conditions in the acute hospital. The categories Protective functions of the skin (b810) and Moving around (d455) should be included in the final version of the comprehensive ICF Core Set for musculoskeletal conditions in the acute hospital.

Acknowledgements

The authors thank all the study participants for patience and collaboration, and thank Dr Paul Cumming for manuscript revisions. We further thank all participating hospitals involved in data collection, Kaiser-Franz-Josef-Hospital, Vienna (Austria), University Hospital Vienna, Vienna (Austria), University Hospital, Zurich (Switzerland), University Hospital, Heidelberg (Germany), and Hannover Medical School, Hannover (Germany). The project was supported by the German Ministry of Health and Social Security (BMGS) grant no. 124-43164-1/501 and by the LMUinnovativ project Münchner Zentrum für Gesundheitswissenschaften, (TP 1).

References