The use of the International Classification of Functioning,Disability and Health to classify the factors influencing mobility reported by persons with an amputation: An international study

Abstract

Background:

Amputation of lower limb results in limitations in mobility which are amenable to multiple rehabilitation interventions. The challenges faced by the persons with lower limb amputation vary internationally. The International Classification of Functioning, Disability and Health provides a common language to describe the function of persons with lower limb amputation across various countries.

Objectives:

This article reports the concepts in mobility important to persons with lower limb amputation across six countries using the International Classification of Functioning, Disability and Health.

Study design:

Qualitative study using focus groups and individual interviews.

Methods:

Focus groups and individual interviews of persons with lower limb amputation were organised across six countries to identify the issues faced by patients with an amputation during and after their amputation, subsequent rehabilitation and on an ongoing basis in their daily life. Meaningful concepts were extracted from the responses and linked to suitable second-level and where applicable third-level International Classification of Functioning, Disability and Health categories. International Classification of Functioning, Disability and Health categorical frequencies were analysed to represent the prevalence and spread of International Classification of Functioning, Disability and Health categories by location.

Results:

A total of 133 patients were interviewed. A large percentage (93%) of the identified concepts could be matched to International Classification of Functioning, Disability and Health categories for quantitative analysis.

Conclusion:

The important concepts in mobility were similar across different countries. The comprehensiveness of International Classification of Functioning, Disability and Health as a classification system for human function and its universality across the globe is demonstrated by the large proportion of the concepts contained in the interviews from across the study centres that could be matched to International Classification of Functioning, Disability and Health categories.

Clinical relevance

The activity and participation restrictions faced by a person with lower limb amputation vary internationally and are amenable to multiple rehabilitation interventions. The International Classification of Functioning, Disability and Health may provide a common language to report and quantify the various concepts important to the patient in their rehabilitation journey.

Keywords

Developing countries International Classification of Functioning Disability and Health mobility outcome measurement patient perspective prosthetics prosthetics and orthotics in developing countries rehabilitation rehabilitation of amputees

Background

Lower limb amputation causes significant impairments that result in activity limitation and participation restriction for the individual.¹ The aim of rehabilitation is to reverse most of these restrictions aided by a variety of interventions, in the majority of cases by the provision of an ideal prosthesis. Any attempt to develop an outcome measure to assess changes with rehabilitation in a person with lower limb amputation should take into account factors considered from the perspective of the person or persons with lower limb amputation.

Outcome measures are intended to measure the impact of interventions in rehabilitation programmes. Quantification of functional improvement assists in demonstrating the effectiveness of rehabilitation programmes, funding bodies to allocate appropriate resources to the programmes, compare the various models of rehabilitation care for persons with an amputation and compare outcomes using different prosthetic components. A large number of outcome measures are used to gather information on mobility outcomes for individuals following an amputation. The most commonly used measures include the mobility section of the Prosthesis Evaluation Questionnaire (PEQ-MS), walking tests and timed up and go test, Locomotor Capabilities Index, L test of functional mobility, Rivermead Mobility Index, Amputee Mobility Predictor and the Functional Independence Measure. While some of the instruments like Locomotor Capabilities index² and the Special Interest Group on Amputation Medicine/Dutch Working Group on Amputations and Prosthetics (SIGAM/WAP)^3,4 have been cross-validated in multiple languages, a significant proportion of the outcome measures are not available in languages other than English. There is no consensus on the best mobility assessment to use in a clinical rehabilitation setting⁵ and a lack of scientific evidence to guide the selection and interpretation of outcome measures.^6,7

The lack of a ‘gold standard’ for the measurement and assessment of mobility outcomes for persons with amputation in the rehabilitation setting is problematic because it reduces the ability to meaningfully compare and interpret data and outcomes internationally and across studies.⁸ There is a need for a simple, sensitive and valid measure of mobility based on a common reference framework or universal language that clinicians can use internationally.⁹

The patient perspective should be included to ensure content validity of any measure that is to be developed.^10–12 Many assessment tools are developed from the perspective of the clinician, but these perspectives do not always correlate with the perspectives and goals of the patient.¹³ In rheumatoid arthritis, less than 40% of concepts considered relevant from the patient perspective were included in commonly used patient outcome measures.¹⁴ The loss of limb is a unique and individual experience¹⁵ and hence the amount of function that the person expects to regain from rehabilitation will vary depending on premorbid function, reason for and aetiology of amputation, age and geographic location of the person with lower limb amputation.

There is evidence that the quality of the perceived result of amputation and the prosthetic management correlate with the function of the prosthesis and the ability of the person with a lower limb amputation to fulfil social interaction and activities.¹⁶ Currently, an outcome measure which encompasses the needs of the complete physical domain of persons with amputation is missing. As outlined by Gallagher et al.,¹⁷ ‘improved understanding of environmental barriers and challenges, activity limitations and participation restrictions experienced by individuals with major limb amputation is a critical step in informing evidence-based service delivery, intervention and policy in order to improve outcomes for this group’.

Focus groups are a form of group interview that uses the interaction between the participants of the group to generate data. Their use is well established in qualitative research to develop outcome tools.^18–20 Individual interview is another method of collecting qualitative data and provides a more in-depth view of experiences and feelings of the participant and may be especially useful when gathering information about sensitive topics.²¹

The International Classification of Functioning, Disability and Health (ICF), one of the World Health Organization (WHO) family of international classifications, provides a universal language for comparing human functioning around the globe.^22,23 The ICF conceptualises a person’s level of functioning as a dynamic interaction between their health condition(s), environmental factors and personal factors.²² Function and disability in the ICF framework are described across the domains of body structures, body functions, activities and participation and environmental factors. Personal factors are not coded in the current version of the ICF. Each domain is hierarchically arranged into chapters, second-level, third-level and fourth-level categories with an increasing number of integers in the codes to increase the specificity of the construct that is coded. The ICF has been field tested widely internationally²⁴ and is available in multiple languages. Hence, it is very useful to categorise functional impairments that are faced by persons with lower limb amputation across the globe.^25,26 An international project group is currently developing a mobility assessment tool based on the ICF.²⁷

The purpose of this study was to explore the aspects of functioning especially related to mobility relevant to persons with lower limb amputation and to quantify them using the ICF as part of developing a mobility assessment tool based on the ICF that could be used for this population to measure outcomes of rehabilitation.

Methods

To determine the patient perspective, a number of focus group interviews or individual interviews were organised for patients with an amputation. The inclusion criteria for the focus groups were anyone with a lower limb amputation at or above the ankle level who did not have significant cognitive impairment and who was able to participate in either focus groups or individual interviews. There were seven focus groups across the various centres involving 50 participants. Information was collected from other participants through individual interviews. Demographic data were collected in paper form and the interviews were digitally recorded and transcribed verbatim by a research assistant. The participants included those attending inpatient or outpatient rehabilitation services in centres across six different international sites in Argentina, Australia, Austria, China, Germany and the USA. The study was conducted between August 2013 and January 2014. The initial approval was obtained through the South West Sydney Local Health District Ethics Committee. Ethical approval was also obtained for each venue according to the local protocol and consent was obtained from each participant. The researchers leading the interviews in various centres were clinicians involved in the rehabilitation of persons with lower limb amputation including physiotherapists, physical medicine and rehabilitation specialists, clinical psychologists and rehabilitation researchers with a social science background. The interviews were conducted across a variety of settings including tertiary hospitals both in public and private health, university clinics, community centres and participants’ homes. Regular meetings with participating centres through Skype and blackboard were held. The translations into English were performed in each of the study centres by the lead researcher.

The participants were asked the following open-ended questions either in English or in their primary language as part of their interview:

If you think about your body, what functional problems do you have?

If you think about your body, where are your biggest problems?

If you think about your daily life, what are your biggest problems?

If you think about your environment, factors in your surroundings, and your living conditions, what do you find …

helpful or supportive?

cumbersome?

If you think about yourself, what is relevant for the way with which you handle your disease?

If you think about your ability to move around, what are you biggest problems.

Further questions were asked and clarifications were given to the participants through examples if they had difficulty understanding the questions and to facilitate conversation. The questions presented to the participants were based on the questions used in patient focus groups for the development of ICF Core sets for specific conditions^28–32 and then refined by a consultative process involving the researchers at the participating international sites. The questions were formulated to explore the concepts across the different domains in the ICF. Thus, information was gathered on problems not related to mobility as well and was coded to obtain a comprehensive picture of the functional goals the participants hoped to achieve. In choosing the participating sites, attention was given to include sites from different WHO regions and different cultures to ensure a broad multinational view was obtained. Unfortunately, a study partner could not be obtained from the continent of Africa.

The first and the second authors who both have experience in using the ICF including linking items^1,33,34 then analysed the transcripts and identified meaningful concepts that were subsequently linked to the most appropriate ICF category according to established linkage rules. For interviews done in a language other than English, the translated transcripts were used for analysis and linking. The concepts were linked to a third-level ICF category if possible. For example, if the patient reported that one of the biggest problems they have in their daily life is to get up from a low chair that concept is matched to category d4104, getting into and out of a standing position or changing body position from standing to any other position, such as lying down or sitting down. A quantitative analysis was carried out to measure the number of times a particular category appeared in the consolidated list of codes as well as for each of the individual study centres.

Results

A total of 133 patients from six countries participated in the study. Table 1 shows the demographics of the participants across five centres. There were 24 participants from Argentina. We unfortunately do not have extensive demographic data from Argentina. The focus groups from Argentina came from three different parts of the country each unique in the socioeconomic status of the subjects, geography, services and support available. There were eight participants from Provinces in the North where there is a high percentage of indigenous population with low insurance coverage and much lower socioeconomic status compared to the rest of the country. The climate is hot with hills and jungles and there are no specialised teams available for rehabilitation of people with lower limb amputation. There were nine participants from the middle of the country where the incomes are higher and the insurance coverage is better. The climate is milder and the land is flat. There were highly specialised rehabilitation teams available to facilitate rehabilitation post-amputation. There were seven participants from the southern provinces, where the landscape and climate are inhospitable and accessibility is less. The population density is low, the incomes belong to the middle socioeconomic range and the insurance coverage is better than the northern provinces.

Table 1.

Demographics.

	Austria	Australia	China	Germany	USA
Average age	65	56	31	60	61
Age range	47–80	30–80	6–50	43–79	51–73
Average time (months)	38	78	25	143	157
Time range (months)	2–444	3–413	1–85	7–612	6–564
Gender
Male	14	24	20	7	11
Female	6	1	7	10	9
TT amputation	15	17	7	7	7
TF amputation	5	5	3	10	13
Other amputation	0	3	17	0	0
Total no. of subjects	20	25	27	17	20

TT: trans tibial; TF: trans femoral.

One half of the participants had amputation secondary to vascular disease, 47 patients had traumatic causes and the rest of them had amputation secondary to other causes like osteomyelitis or neoplasm. The majority of the patients were prosthetic users. A total of 1736 concepts were identified. A large percentage (93%) of the concepts could be linked to a second-level ICF category; 55% of these linked concepts could be linked to ICF third-level category. Table 2 shows the distribution of matched and unmatched concepts across the study centres.

Table 2.

Frequency distribution of matched and unmatched concepts.

	Concepts matched to ICF categories		Concepts not matched to ICF categories		Total
	Number	Percentages	Number	Percentages	Total
Argentina	170	92.4	14	7.6	184
Austria	92	78.63	15	12.8	117
Australia	676	98.4	11	1.6	687
China	92	80	23	20	115
Germany	280	93.02	21	6.98	301
USA	336	95.45	16	4.55	352
Total	1646	94.8	90	5.2	1736

ICF: International Classification of Functioning, Disability and Health.

The linked second-level categories included 28 in the domain of body function, 41 in the domain of activity and participation, 27 in the environmental factors domain and 5 in the body structure domain. Tables 3 and 4 show the most frequently occurring concepts in the domains of body function and body structures and the domain of environmental factors. The most frequently occurring items in the domain of activity and participation were walking on different surfaces, climbing, recreation and leisure. Tables 5 to 7 show details of the ICF categories identified.

Table 3.

Distribution of most frequently occurring environmental factors across the study centres.

ICF code	Description of the ICF category	Argentina	Austria	Australia	China	Germany	USA
e1150	General products and technology for personal use in daily living	1	0	4	6	0	5
e1151	Assistive products and technology for personal use in daily living	6	0	28	0	5	5
e1201	Assistive products and technology for personal indoor and outdoor mobility and transportation	3	6	15	2	11	13
e1500	Design, construction and building products and technology for entering and exiting buildings for public use	5	4	1	1	2	4
e1501	Design, construction and building products and technology for gaining access to facilities inside buildings for public use	1	1	7	1	1	2
e1550	Design, construction and building products and technology for entering and exiting of buildings for private use	1	0	9	0	0	0
e1551	Design, construction and building products and technology for gaining access to facilities in buildings for private use	4	8	9	0	8	5

ICF: International Classification of Functioning, Disability and Health.

Table 4.

Most frequently occurring categories in the domain of body structure and body function.

ICF category	Argentina	Austria	Australia	China	Germany	USA
b126 (Temperament and personality functions)	3	1	6	4	7	2
b152 (Emotional functions)	2	0	5	0	2	0
b280 (Sensation of pain)	6	1	26	6	10	10
b530 (Weight maintenance function)	0	0	7	0	3	6
b710 (Mobility of joint functions)	2	0	4	3	0	0
b730 (Muscle power functions)	0	0	5	3	0	6
Involuntary movement reaction function	3	1	10	0	2	0
b810 (Protective functions of the skin)	0	0	18	4	4	8
s750 (Structure of lower extremity)	0	0	5	1	2	1

ICF: International Classification of Functioning, Disability and Health.

Table 5.

Distribution of concepts other than mobility in the activity and participation domain.

Chapters (activities and participation domain)	Argentina	Austria	Australia	China	Germany	USA
Self-care	7	3	56	9	5	10
Domestic life	2	5	34	1	21	26
Major life areas	8	0	16	3	8	14
Community, social and civic lives	5	5	28	1	26	21

Table 6.

Country-wise distribution of mobility concepts.

Activities	Argentina	Austria	Australia	China	Germany	USA
Changing and maintaining position	2	0	39	6	15	14
Carrying, moving and handling objects	4	0	14	0	7	12
Walking and moving	43	31	153	17	60	76
Moving around with transportation	11	8	35	2	18	18

Table 7.

Country-wise ranking of most frequently occurring third-level ICF categories related to walking and moving.

Concepts related to walking and moving	Argentina	Austria	Australia	China	Germany	USA
Walking long distances	4	–	4	4	5	–
Walking on different surfaces	1	–	1	1	2	1
Walking around obstacles	–	2	–	–	–	–
Climbing	3	1	2	3	1	2
Running	2	3	–	2	3	5
Swimming	–	4	–	–	4
Moving around within home	–	–	3	–	–	3
Moving around outside home and other buildings	5	–	5	5	–	4

Among the concepts in activities and participation domain, the larger proportion of the concepts related to the chapter of mobility across all the study centres (Table 8). The concepts in self-care followed mobility concepts as the most frequently occurring in two of the centres while participation in major life areas which include concepts related to participation in employment and education was more important after mobility in the sample from Argentina. Items in the chapter of domestic life and community, social and civic lives were more frequently found in the analysis of transcripts from Austria, Germany and USA (Table 5).

Table 8.

Count and percentage of concepts related to mobility chapter of ICF.

Country	Total concepts related to mobility	Percentage (rounded) with respect to the total coded concepts
Argentina	60	35
Austria	39	42
Australia	241	35
China	25	27
Germany	100	35
USA	120	35

As an illustration of the quantitative analysis, the concept walking on different surfaces, code d4502 appeared 32 times in the focus groups in Australia, 9 times in German focus groups, 3 times in the groups from China, 13 times in focus groups across the USA and 9 times in the focus groups from Argentina. It appeared 73 times in the consolidated sample (4.43% of the total coded concepts).

Discussion

A large percentage (93%) of the concepts from the focus groups could be linked to ICF items which underlines the breadth of the ICF classification and its inclusiveness of major concepts. This is similar to other studies that have used focus group methodology to identify concepts related to a specific health condition and link these concepts to ICF.^35,36 Concepts that could not be matched to a second-level ICF category included those that were too broad such as participation in activities of daily living, concepts that were not defined like nightmares about amputations or personal factors like courage and acceptance of amputations that were not coded in the current version of ICF. Specific prosthesis-related factors like cosmetics and comfort and procedure-related factors like surgical techniques used for amputation were not matched either. A concept that came up in the interviews which could not be matched satisfactorily to any of the ICF categories but was nonetheless important was the geographic location within their country of residence. People living in remote towns had less access to suitable services and had to either relocate or travel long distances to access appropriate prosthetic services.

The most commonly occurring concepts were in the activities and participation domain especially relating to climbing, moving outside private and public buildings and participation in recreation and leisure. This underlines the importance of these activities to persons with lower limb amputation and their desire to achieve maximum gains and the need to monitor outcomes in these domains during the rehabilitation process. There was one category in the activities and participation domain of changing body position to squatting that appeared only in the focus groups from China. This may also be the case in other parts of the world where squat toilets are commonly used. Different positions like kneeling or sitting cross-legged on the floor are also adopted for prayer in different parts of the world. While this did not emerge in the focus groups, it will be another important consideration when developing a mobility assessment tool that has applicability across different cultures. Another interesting cross-cultural difference was the concept of climbing mountains that emerged only in the focus groups from Argentina. While it is still linked to category d4551, the level of skill that is needed by a person with a lower limb amputation before climbing mountains can be achieved is different to climbing ladders. The concept of climbing mountains was particularly important to the participants from the North of Argentina where 40% of the population belong to indigenous communities and the natural geography is mountainous with jungles. Other participating countries also have high mountains, but this theme did not emerge as they were not specifically included as focus groups as was the case with the Argentinian sample. Measuring performance for items as they are defined in ICF will hopefully reduce the ceiling effects of the outcome measure based on ICF.

Among the environmental factors apart from the prosthesis and other mobility aids affecting mobility, participants across the six centres identified friends and family as strongly influencing their function. The participants, especially from Germany and some from Austria, found peer support groups empowering. This did not emerge in interviews at other sites especially Argentina and China. The participating site in China did not have peer support groups. Argentina has peer support groups for persons with lower limb amputation. The participants were not asked explicitly about their opinion on peer support groups. The variation in interview styles as well as accessibility to resources like peer support could explain why peer support was not recognised as an enabling factor by participants from some study sites. In addition to the variance of data from geographical and cultural differences, there may be variance due to individual interview styles and interpretation of questions. Among the concepts in body function domain, the participants from all the six sites identified pain as an important factor affecting their function. The study centres were across five different continents and we have been able to capture the concepts of mobility and function that are important to people across a wide variety of geographic locations and varied cultures and economic resources. We were able to include in our focus groups people that were in different stages of their rehabilitation, the range of time post-amputation of the participants varied from 1 month to 51 years. We also had participants with a range of functional capacities from prosthetic nonusers dependent on a carer for activities of daily living to highly skilled prosthetic users who participated in competitive sports.

One of the drawbacks of the study was that when the focus groups were performed in languages other than English the matching of concepts was not done in the initial transcript but in the translated one which may have resulted in concepts being missed or misunderstood. We did not have a study centre in Africa and hence have missed out expectations and challenges that the persons with lower limb amputation face on that particular continent. The inclusion of participants from areas of civil unrest or those geographic locations where environmental disasters led to significant prevalence in amputation might result in more concepts of significance to persons with a lower limb amputation being identified.

Whether the data from particular centres were obtained mainly by individual interviews or by focus groups depended on the preference of the participants that were interviewed and on the experience of the researcher at that particular centre. A detailed analysis of saturation of concepts was not done for the purpose of this article as the aim was to find the most frequently occurring ICF categories so that they could be used in the development of the mobility tool. A raw analysis of the data does indicate a saturation of concepts for an individual study centre for the last focus groups/individual interviews conducted.

A recent qualitative study in patients who have undergone lower limb amputation clearly shows the importance of appropriate education and peer support programmes to encourage more active and informed participation of persons with lower limb amputation in their rehabilitation.³⁷ This theme did emerge in the focus groups where the participants gave significant value to the education that they received from the health care professional pre- and post-amputation.

Conclusion

The comprehensiveness of ICF as a classification system for human function and its universality across the globe is demonstrated by the large proportion of the concepts contained in the interviews from across the study centres that could be matched to ICF categories. This indicates that ICF-based tools to assess changes in mobility and function resulting from a rehabilitation programme and that are relevant to the person with a lower limb amputation are feasible and will have international application.

Footnotes

Acknowledgements

Acknowledgements to the following who contributed to the data collection and other parts of the study:

Prof. Veronica Fialka-Moser, Department of Physical Medicine and Rehabilitation, Medical University of Vienna, Vienna, Austria.

Prof. Chengqi He, Dr. Shasha Li, Yonghong Yang, Pu Wang and Lin Yang, from West China Hospital of Sichuan University.

Prof. Xiaolin Huang and Prof. Tao Xu, from Tongji Medical Colleague, Huazhong University of Science and Technology.

Prof. Dan Tang and Dr. Xiaoqian Deng, from Guangdong Province Work Injury Rehabilitation Hospital.

Prof. Huifang Wang, Dr. Jianhua Lin and Jia Hu, from Shanghai Sunshine Rehabilitation Center.

Sara Jerousek,Project Manager, CROR. Center for Rehabilitation Outcomes Research,Rehabilitation Institute of Chicago 345 E. Superior, Chicago, IL 60611.

Susan Deems Dluhy DPT Physical Therapist, Max Nader Lab for Rehabilitation Technologies and Outcomes Research, Rehabilitation Institute of Chicago, Chicago, IL.

Prof. Allen W Heinemann, PhD Director, Centre for Rehabilitation Outcomes Research Professor, Department of Physical Medicine & Rehabilitation, Northwestern University, Chicago, IL.

Christoph Egen, Department of Physical Medicine and Rehabilitation, University of Hannover, Germany.

Ms Damiana Pacho,British hospital, Buenos Aires, Argentina.

Prof. Hugh Dickson, Liverpool hospital and UNSW, Australia.

Author contribution

All authors have contributed significantly in the study design, implementation and write up phases of the study.

Declaration of conflicting interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship and/or publication of this article.

Funding

The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by Össur Deutschland GmbH and Otto Bock Healthcare Products GmbH.

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