University of Groningen The Measurement and Prediction of Physical Functioning after Trauma de Graaf, Max Willem

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The Measurement and Prediction of Physical Functioning after Trauma

de Graaf, Max Willem

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Chapter 1

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General Introduction

Measurement instruments play a key role in making diagnoses, prognoses and decisions in modern medicine. The field of trauma surgery is no exception. Whether one deals with a hemodynamically unstable patient or the recovery of physical functioning after a fractured elbow, measurements form the basis of a good understanding of the problem at hand.

In this thesis, many different aspects of a measurement instrument will be addressed. The focus lies specifically on evaluating the quality of a measure-ment instrumeasure-ment with regard to its capability to measure physical functioning in patients with a broad range of traumatic injuries. Specific characteristics of this population, such as heterogeneity of patient characteristics, types of injuries and injury severity, pose additional challenges to making and inter-preting measurements that are correct for the entire population.

Before the matter of the evaluation of measurement instruments is discus-sed in greater detail, it should be noted what measurement instruments are used for. They serve the process of understanding problems. It is therefore relevant to be aware that there are various kinds of problems (e.g. contexts of problems) that may be identified in the first place. Specific contexts of problems require a unique approach. Knowledge of these contexts may help place the findings of this thesis in a broader context. To this end, some back-ground on the various contexts of problems will first be provided.

Contexts of problems

Complex problems are fundamentally different from complicated problems, and require a fundamentally different approach in order to solve them, is what Kurtz and Snowden said when they developed the Cynefin framework in 1999.1, 2_{Cynefin is a conceptual framework that aids in}

under-standing problems and subsequent decision-making, by identifying contexts that require a different approach. In the framework four groups of contexts can be identified, ranked by the “amount” of uncertainty involved: simple/obvi-ous, complicated, complex and chaotic contexts.1_{Kurtz and Snowden pointed}

out that each context had its unique aspects, and that problems encountered within each of the different contexts would require a unique approach (Figure 1).1, 2_{The different contexts will be explained below.}

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These contexts are generally accepted as “knowledge”. An example of a simple/ known context is the case of a 30-year-old female patient that fell from her bike and hit a sharp object with her ankle. This yielded a cut wound of 3 cm near the ankle. Cause and effect are clear. The solution of eliminating the defect logically follows, for example by using sutures.

Complicated/knowable contexts express a higher degree of uncertainty

than simple/known contexts. For a complicated problem there is a wide vari-ety of possible causes that can create an effect.1, 2_{Similarly to simple/known}

contexts, the set of causes are directly related to the effect and do not change over time or between individuals.2_{This is usually the domain of “experts”,}

as all possible causes are often only known by a select group of people.2_An

example of a complicated problem is a 20-year-old football player with an unstable ankle fracture he got after a tackle. Kurtz and Snowden pointed out that complicated problems can be “solved” by analyzing the problem and

reducing the possible causes.1-3_{The expert involved is a trauma surgeon that}

has the specific knowledge required for such problems. As there are many available treatments for ankle fractures, the fracture components and presence of accompanying injuries such as syndesmosis injuries have to be analyzed. A thorough understanding of the fracture components and the cause of the instability enables the surgeon to reduce the possible causes of the instability and choose a suitable treatment, for example by using plate osteosynthesis.

Problems become complex in the hypothetical case that the cause of the instability in the fracture cannot be deduced from observing the fracture components. Similarly to a complicated context, in a complex context a vari-ety of causes can create a specific effect.2_{However, in a complex context the}

number of causes and the strength of their relationship to the effect are not clear.4_{Often (a part of) the causes are non-observable latent factors that may}

vary from individual to individual.4_{An example of a complex context is the}

consideration of what treatment is most beneficial to the quality of life of a 59-year-old female with a nonunion after a right-sided ankle fracture. She has pain in the ankle and problems with walking and performing her activities of daily living. She also has obesity, diabetes mellitus type 2, and a status after a transient ischemic attack in the left hemisphere. In such complex a complex situation, nobody definitively knows which treatment is right. Kurtz and Snow-den explicated that in such complex contexts the causative factors involved have to be probed and explored in order to reveal enough of the underlying

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causality, so that a sufficiently informed decision can be made.2, 4_{In relation}

to our example, the fracture and previous treatment itself should be evalu-ated, but also the extent of her problems with walking and performing daily

activities, management of chronic health conditions, coping style, expected recovery, occupation, personal life goals and possibly many other factors should be evaluated in an exploratory manner. In chaotic contexts there is no perceivable relation between cause and effect.1_{For the sake of this}

introduc-tion, the chaotic context will not be further discussed.

In healthcare, whether it is a general practice in a small village or a major university medical center, complex and complicated problems are both abun-dant.3 As described previously, complex problems require a different approach than complicated problems. In complex contexts, analytic reduction of the

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possible causes, rather than exploration of the possible causes, is problematic.4, 5_{Inappropriate reductionism may lead to oversimplification of the problem}

and inappropriate conclusions.4, 5_{Referring to the complex example of the}

patient with a nonunion of a fractured ankle, reduction of the causative factors involved by concluding the bone has not healed, so therefore an additional surgical intervention is required, oversimplifies the problem and does not do justice to other factors involved. It can be concluded that healthcare providers should be aware of the complexity of medical contexts, and embrace rather than reduce and ignore its presence.3, 4

Biomedical and biopsychosocial model

In the past age of medicine, the biomedical model has been the predo-minant approach to solve clinical problems.3, 6_{The underlying hypothesis of}

the biomedical model is that all disease is a result of cellular abnormalities.6

This approach has led to a very detailed understanding of human anatomy and (patho)physiology, including the discovery of the human genome and the invention of antimicrobial agents.3, 6-8_{Though the exceptionally detailed}

understanding of these concepts is clearly relevant for many diseases, it does not appear to be the panacea to all medical problems. The biomedical model does not take multifactorial diseases or psychiatric diseases into account.6, 9

William Osler (1848-1919) already noted that “It is much more important to know what sort of a patient has the disease, than to know what disease the patient has”.10_{He meant that many more factors influence a patient’s health}

and accompanying medical decisions besides the observable disease. By realizing the complexity of medical problems, Osler was ahead of his time. In the 20th_{century criticism of the biomedical model increased, leading to the}

emergence of the biopsychosocial model,9_{a novel model that described that}

disease may be caused or influenced by biological, psychological and social factors, matching the determinants of health of the World Health Organiza-tion’s definition of health.11

How should we define health?

In 1948, the World Health Organization (WHO) defined health as “a state of complete physical, mental and social well-being, and not merely the absence of disease or infirmity”.11_{At the time of its introduction the definition was}

progressive and innovative compared to the previous definition, which defined health as “the absence of disease”.12_{The new definition expanded the possible}

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causes that affected health. However, in recent decades this definition has increasingly been criticized for being negative and reductionistic.6, 12, 13_The

definition implies that any person that is not in a state of complete physical, mental and social well-being is “unhealthy”.12

In 2011, Huber et al. proposed changing the definition to “the ability to adapt and self-manage”.12_{This definition was clearly broader than that of the}

WHO, and explicitly did not mention factors that would determine health, as these factors and their importance may vary per individual. One could say that Huber’s definition recognized and embraced the complexity of health.

Huber et al. suggested that the measurement of health status may be guided by conceptual frames that operationalize important aspects of health and relate to the ability to adapt and self-manage, such as the several classi-fication systems of the WHO.12_{The International Classification of}

Functio-ning, Disability and Health (ICF) is the classification system of the WHO that describes and relates health and functioning related problems.14_{In the ICF}

classification, three interconnected aspects of functioning and its problems are identified: 1) Body Function and Structure, 2) Activities and 3) Participation (Figure 2).14_{These aspects are related to contextual factors (environmental,}

personal). The domain Body Function and Structure refers to the anatomic and physiological functions of the human body (such as joint, muscular, respiratory function). The domain Activity refers to the execution of tasks or actions by an individual, such as doing household chores or sports. The Parti-cipation domain refers to involvement in life situations, such as taking part in a discussion or playing a game with others. The ICF classification describes the domains that should be assessed to evaluate functioning, but does not describe how the domains should be measured.15

Measurement in healthcare contexts

Measurement of health outcomes is essential in scientific research and clinical practice.16_{Taking into account that many medical problems are}

complex, measurements should honor the complexity of the domain of inte-rest. Traditionally, outcome of treatment has been assessed solely by means of measurements such as vital signs, range of motion of an affected joint, bone healing assessed by radiographic imaging, laboratory tests and morta-lity. The problem with these traditional outcome measures is that they are simple outcomes that explicitly relate to the ICF Body Functions and Structure

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domain. However, they generally do not reflect the complex domains of Acti-vity or Participation. Whether there are problems in the ActiActi-vity and Participa-tion domains depends largely on a patient’s individual situaParticipa-tion. For example, a fractured ankle may pose much greater problems within these domains for a professional football player than for someone with an office job. Due to this individual dependence, patients themselves may provide the most accurate information to evaluate the Activity and Participation domains. Due to the shift in focus of what health is, the traditional clinical ways of measuring health and the effects of treatment are increasingly accompanied by patient-repor-ted outcome measures (PROMs), which are better suipatient-repor-ted for probing complex domains.17

PROMs are measurement instruments that are directly reported by a patient (i.e. the responses are not interpreted by a physician or anyone else).18

Though a PROM may be any type of measurement instrument, most are in the form of a self-reported or interviewer-administered questionnaire. PROMs provide unique information that cannot be obtained with traditional measu-res of health outcome. The key purpose of a PROM is to capture patients’

own perception of health or specific aspects of health.17_{In complex contexts,}

PROMs can be used to probe the domains of interest. Examples of constructs that are frequently assessed with PROMs are functional status, health status and quality of life.16

Figure 2: The International Classification of Functioning Disability and Health

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PROMs provide information that is useful in individual patient care, for example by assessing patients’ individual functional outcome after trauma. One can evaluate whether a patient recovers as expected or has reached a normal level of functioning. PROMs provide valuable information at other levels too, like when comparing treatment outcomes in research, or as quali-ty-control instruments for benchmarking performance of individual health-care providers and institutions.17

PROMs are increasingly used to capture perspectives of patients in research and clinical practice. To date, use of PROMs is a requirement for clinical trials funded by the US Food and Drug Administration (FDA).18_{In addition, since}

April 2009 the routine collection of PROMs is required by the National Health Services (NHS) in the United Kingdom to measure and improve clinical quality of specific elective surgical procedures such as hip and knee replacement and inguinal hernia repair.17, 19

Quality of health measurement instruments

Health measurement instruments, including PROMs, provide information from which clinical or organizational decisions are made.16, 20_These

instru-ments should therefore provide reliable and valid measureinstru-ments,16_otherwise

biased or inaccurate results are obtained which may lead to false conclusions and incorrect decisions. Since the constructs assessed with PROMs are often subjective and not directly observable, it is very important that the quality of the instrument is warranted.16_{To determine whether a PROM is of high}

quality, its clinimetric measurement properties have to be evaluated.16, 20_These

properties can be divided into several aspects: validity, reliability, internal consistency and responsiveness.21, 22_{Definitions of these aspects are provided}

in Table 1. It is important that the studies that evaluate these measurement properties are of high methodological quality, so that the conclusions regar-ding the instrument’s clinimetric properties are solid.16_{The COSMIN checklist}

(COnsensus-based Standards for the selection of health status Measurement INstruments) was recently developed; it contains quality criteria for studies that evaluate these measurement properties.22-24_{The authors of the COSMIN}

checklist have also provided guidance for researchers on how measurement properties should be evaluated.25

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Trauma and injury-related disability

A specific group of patients that suffers from disability and problems with physical functioning are those who have sustained physical trauma. Trauma is the largest cause of death in adults younger than 45 and is frequently consi-dered an important cause of disability.26_{Due to a reduction in trauma-related}

mortality and an increased lifespan, the number of people living with inju-ry-related disabilities is growing.27_{In the Netherlands, the annual number of}

injured patients treated at emergency departments approaches 1.1 million.26

A Dutch study showed that injured patients who were hospitalized for more than three days still experienced many problems two years after the injury: 60% still had pain, more than 50% had problems with mobility and daily activities, and more than 25% suffered from depression or anxiety.28_{Many patients are}

not able to return to work due to their disabilities following injury, which has significant consequences for both individuals and society. The financial bill for society is high: total costs are estimated at 5.30 billion euros, of which 1.55 billion is direct medical care.29_{Insight into the determinants of both short-}

and long-term disability in a broad population of trauma patients can be used to prioritize the development of preventive policies and improve trauma care. In trauma, clinical outcome and treatment effectiveness have often been assessed solely by means of traditional outcome measures (i.e. range of motion, vital signs, injury severity score, mortality).30, 31_{These measures have}

shown to correlate poorly with patients’ view of their functioning and are poor determinants of long-term disability.32_{The reason that traditional outcome}

measures correlate poorly with functional outcome is that these outcomes are solely representative of the Body Functions and Structure domain of the ICF model. Physical functioning as perceived by the patient is not measured with the traditional outcomes.31_{They evaluate even less to which extent patients}

are bothered by their injuries and how the disability relates to their functio-ning and participation.

To date, limitations in physical, mental and social functioning after trauma have been scarcely studied. This is partly due to a lack of well-evaluated measu-rement instruments.33, 34_{While a large number of PROMs have been designed}

to evaluate aspects of physical functioning after trauma, many have not been evaluated in conformity with the quality criteria stated in the aforementioned COSMIN guidelines, or have shown insufficient performance in one or more clinimetric properties.35-40

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Developed instruments range from ones that evaluate very specific constructs (such as knee function) to instruments that evaluate very gene-ral constructs (such as genegene-ral health status). The choice of an appropriate measurement instrument should depend not only on the construct of interest but also on the population that is investigated.41_{A measurement instrument}

should be suitable for the specific target population.41_{The population of}

trauma patients is heterogeneous, since it exhibits a broad spectrum of inju-red body regions and injury severities. Hence when a broad range of injuinju-red patients is evaluated it is important that the instrument is applicable to the entire population. A PROM that can be used to evaluate physical functioning and that may be applied among a broad range of injured patients is the Short Musculoskeletal Function Assessment (SMFA).42

Short Musculoskeletal Function Assessment

In 1999, Swiontkowski et al. developed the SMFA as an instrument to assess physical functioning in patients with a broad range of musculoskeletal condi-tions.42_{The SMFA has been designed as an instrument that is not too specific,}

nor too general, and is therefore considered suitable for heterogeneic samples such as trauma patients.42, 43_{The SMFA contains 46 items and was developed}

as a shorter alternative to the 101-item-long Musculoskeletal Function Assess-ment.42_{The SMFA contains items that assess the physical functioning of the}

entire human body, problems with daily activities and psychological aspects of functioning. The SMFA has recently been translated into Dutch (SMFA-NL, Appendix 1).44

Treatment of trauma patients and recovery of physical functioning after trauma are complex contexts. Recalling from Kurtz and Snowden, in such contexts the causative factors involved have to be probed, in order to be able to make sufficiently informed (treatment) decisions.2, 4_{The SMFA may be eligible}

to probe various domains of physical functioning, in order to gain insight into the (recovery of) physical functioning of trauma patients. However, the clini-metric properties of the SMFA-NL have not been evaluated in a population consisting of patients with a broad range of acute traumatic injuries. Before any PROM can be used in another “new” patient population, the measurement properties of the instrument in this “new” population have to be evaluated.25

Hence an analysis of its clinimetric properties is needed before the SMFA-NL can routinely be used in patients with acute injuries.

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Due to the nature of PROMs, the scores derived from the instrument may not be readily interpretable.45_{For example, it may not be directly clear which}

score represents a “healthy” or “normal” state. Scores of a PROM do not readily show which change in score may be considered meaningful either.45_{This poses}

an additional challenge for clinicians: interpretation of the data derived from PROMs. An appropriate interpretability of a (change in) score is a prerequisite for using a PROM in clinical practice. In order to make the scores interpreta-ble, additional information is necessary to place single scores and changes in scores within a clinical context.25

Aim and outline of this thesis

The aim of this thesis was to evaluate the quality of the SMFA-NL questi-onnaire with regard to its ability to assess physical functioning in patients that sustained a broad range of acute traumatic injuries. The thesis is divided into two parts. The aim of the first part was to evaluate the clinimetric properties (reliability, internal consistency, validity and responsiveness) of the SMFA-NL. The aim of the second part was to investigate the interpretability and prog-nostic performance of the SMFA-NL with regard to (recovery of) physical functioning after trauma.

Part I – Clinimetric properties of the SMFA-NL

The clinimetric properties of the SMFA-NL have not yet been assessed in patients with a broad range of acute traumatic injuries. Establishing these measurement properties is essential, as it explains the extent to which the SMFA-NL yields reliable and valid measurements of physical functioning in trauma patients. To evaluate whether the SMFA-NL can be used to assess functional status of trauma patients, various measurement properties will be evaluated according to the COSMIN criteria. In Chapter 2, the structural

vali-dity and internal consistency of the SMFA-NL were evaluated. In this chapter the number of latent constructs that may be measured using the SMFA-NL and the configuration of items that represent these constructs were evaluated using confirmatory factor analysis. In Chapter 3, the test-retest reliability,

construct validity, and responsiveness of the factor structure that was found in Chapter 2 were evaluated.

Part II – Interpretability and clinical application of the SMFA-NL

Part II of this thesis is focused on the clinical relevance and interpretability of the measurements taken with the SMFA-NL. A measurement instrument

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that has good clinimetric properties is not necessarily a well-interpretable instrument. The aim of Chapter 4 was to create a benchmark for what is a

normal level of physical functioning by obtaining normative data of the Dutch population. In Chapter 5, pre-injury physical functioning of trauma patients

was evaluated and compared to the level of physical functioning of the Dutch population.

When trauma patients recover from their injuries, the scores on the subsca-les of the SMFA-NL may change over time. Which change in score may be regarded as clinically important is unclear though. In Chapter 6 the smallest

change in SMFA-NL score that is considered important to patients was evalu-ated for each subscale.

Measurement and interpretability of (change in) physical functioning are important to patients and physicians to justify the clinical use of an instru-ment. In Chapter 7 it was investigated whether recovery of physical

func-tioning after trauma can be predicted accurately. A prognostic model was developed with which functional recovery after trauma can be predicted using the SMFA-NL.

Chapter 8 provides a general discussion of the studies presented in this

thesis. Several theoretical and practical implications of the research and suggestions for future research are given.

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Table 1: Definitions of clinimetric properties.21

Clinimetric property Definition

Validity The degree to which a PROM measures the construct* that is in-tended to be measured.

Construct validity The degree to which the scores of a PROM are consistent with hy-potheses (for example with regard to other PROMs or differences between relevant groups), based on the assumption that the PROM validly measures the construct* that is intended to be measured. Structural Validity The degree to which the scores of a PROM are an adequate

reflecti-on of the dimensireflecti-onality of the creflecti-onstruct that is measured Reliability The degree to which the PROM is free of measurement error.

Test-retest reliability The extent to which scores for patients who have not changed, are the same for repeated measurements.

Internal consistency The degree of interrelatedness among the items of a PROM, or its subscales.

Responsiveness The ability of a PROM to detect change over time in the construct* that is measured

Interpretability** The degree to which one can assign qualitative meaning to a PROM’s quantitative score or change in score.

*Construct: Construct refers to the theoretical concept that is intended to be measured, e.g. physical functioning for the SMFA-NL. ** Interpretability is not a formal measurement property, but regarded an important aspect of a measurement instrument.

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11. Grad FP. The preamble of the constitution of the World Health Organization. Bull World Health Organ 2002; 80: 981-981.

12. Huber M, Knottnerus JA, Green L, et al. How should we define health?. BMJ 2011; 343: d4163.

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18. US Department of Health and Human Services FDA Center for Drug Evaluation and Research, US Department of Health and Human Services FDA Center for Biologics Evaluation and Research and US Department of Health and Human Services FDA Center for Devices and Radiological Health. Guidance for industry: patient-reported outcome measures: use in medical product development to support labeling claims: draft guidance. Health and Quality of Life Outcomes 2006; 4: 1-20.

19. Devlin NJ, Parkin D and Browne J. Patient-reported outcome measures in the NHS: new methods for analysing and reporting EQ-5D data. Health Econ 2010; 19: 886-905.

20. Mokkink LB, Terwee CB, Knol DL, et al. Protocol of the COSMIN study: COnsen-sus-based Standards for the selection of health Measurement INstruments. BMC Med Res Methodol 2006; 6: 2.

21. Mokkink LB, Terwee CB, Patrick DL, et al. The COSMIN study reached internatio-nal consensus on taxonomy, terminology, and definitions of measurement properties for health-related patient-reported outcomes. J Clin Epidemiol 2010; 63: 737-745.

22. Mokkink LB, Terwee CB, Knol DL, et al. The COSMIN checklist for evaluating the methodological quality of studies on measurement properties: a clarification of its content. BMC Med Res Methodol 2010; 10: 22-2288-10-22.

23. Terwee CB, Mokkink LB, Knol DL, et al. Rating the methodological quality in syste-matic reviews of studies on measurement properties: a scoring system for the COSMIN checklist. Qual Life Res 2012; 21: 651-657.

24. Prinsen CAC, Mokkink LB, Bouter LM, et al. COSMIN guideline for systematic reviews of patient-reported outcome measures. Qual Life Res 2018; 27: 1147-1157.

25. De Vet HCW, Terwee CB, Mokkink LB, et al. Measurement in medicine: Cambridge University Press, 2011.

26. Polinder S, Haagsma JA, Lyons RA, et al. Measuring the population burden of fatal and nonfatal injury. Epidemiol Rev 2012; 34: 17-31.

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27. Van Beeck EF, Larsen CF, Lyons RA, et al. Guidelines for the conduction of follow-up studies measuring injury-related disability. J Trauma 2007; 62: 534-550.

28. Meerding WJ, Looman CW, Essink-Bot ML, et al. Distribution and determinants of health and work status in a comprehensive population of injury patients. J Trauma 2004; 56: 150-161.

29. Meerding WJ, Mulder S and van Beeck EF. Incidence and costs of injuries in The Netherlands. Eur J Public Health 2006; 16: 272-278.

30. Browner BD, Jupiter JB, Krettek C, et al. Skeletal Trauma E-Book: Elsevier Health Sciences, 2014.

31. Oltman R, Neises G, Scheible D, et al. ICF components of corresponding outcome measures in flexor tendon rehabilitation–a systematic review. BMC musculoskeletal disor-ders 2008; 9: 139.

32. Polinder S, Haagsma JA, Belt E, et al. A systematic review of studies measuring health-related quality of life of general injury populations. BMC Public Health 2010; 10: 783-2458-10-783.

33. Gabbe BJ, Williamson OD, Cameron PA, et al. Choosing outcome assessment instru-ments for trauma registries. Acad Emerg Med 2005; 12: 751-758.

34. Gruen R, Gabbe B, Stelfox H, et al. Indicators of the quality of trauma care and the performance of trauma systems. Br J Surg 2012; 99: 97-104.

35. van de Water ATM, Shields N and Taylor NF. Outcome measures in the management of proximal humeral fractures: a systematic review of their use and psychometric properties. Journal of Shoulder and Elbow Surgery 2011; 20: 333-343.

36. Schmidt S, Ferrer M, González M, et al. Evaluation of shoulder-specific patient-re-ported outcome measures: a systematic and standardized comparison of available evidence. Journal of Shoulder and Elbow Surgery 2014; 23: 434-444.

37. Dodd A, Osterhoff G, Guy P, et al. Assessment of functional outcomes of surgically managed acetabular fractures: a systematic review. Bone Joint J 2016; 98-B: 690-695.

38. Eechaute C, Vaes P, Van Aerschot L, et al. The clinimetric qualities of patient-assessed instruments for measuring chronic ankle instability: a systematic review. BMC musculos-keletal disorders 2007; 8: 6.

39. Jia Y, Huang H and Gagnier JJ. A systematic review of measurement properties of patient-reported outcome measures for use in patients with foot or ankle diseases. Quality of Life Research 2017; 26: 1969-2010.

40. Ng R, Broughton N and Williams C. Measuring Recovery After Ankle Fractures: A Systematic Review of the Psychometric Properties of Scoring Systems. The Journal of Foot and Ankle Surgery 2018; 57: 149-154.

41. Mokkink LB, Prinsen CA, Bouter LM, et al. The COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) and how to select an outcome measurement instrument. Brazilian journal of physical therapy 2016; 20: 105-113.

42. Swiontkowski MF, Engelberg R, Martin DP, et al. Short musculoskeletal function assessment questionnaire: validity, reliability, and responsiveness. J Bone Joint Surg Am 1999; 81: 1245-1260.

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43. Bouffard J, Bertrand-Charette M and Roy J. Psychometric properties of the Muscu-loskeletal Function Assessment and the Short MuscuMuscu-loskeletal Function Assessment: A systematic review. Clinical Rehabilitation 2015.

44. Reininga IH, el Moumni M, Bulstra SK, et al. Cross-cultural adaptation of the Dutch Short Musculoskeletal Function Assessment questionnaire (SMFA-NL): internal consis-tency, validity, repeatability and responsiveness. Injury 2012; 43: 726-733.

45. de Vet HC, Terwee CB, Ostelo RW, et al. Minimal changes in health status question-naires: distinction between minimally detectable change and minimally important change. Health and Quality of Life Outcomes 2006; 4: 1-5.

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1 Hoeveel moeite heeft u met het in of uit een lage stoel komen?

Geen moeite Geringe moeite Matige moeite Veel moeite Onmogelijk om te doen

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2 Hoeveel moeite heeft u met het openen van medicijnflesjes of –potjes?

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3 Hoeveel moeite heeft u met het doen van uw dagelijkse boodschappen of anderszins winkelen?

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4 Hoeveel moeite heeft u met traplopen?

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5 Hoeveel moeite heeft u met het maken van een stevige vuist?

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6 Hoeveel moeite heeft u met het in of uit de douche of bad stappen?

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7 Hoeveel moeite heeft u met het makkelijk in slaap vallen?

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8 Hoeveel moeite heeft u met bukken of knielen?

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9 Hoeveel moeite heeft u met het gebruik van knopen, drukknopen, haakjes of ritsen?

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10 Hoeveel moeite heeft u met het knippen van uw eigen vingernagels?

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11 Hoeveel moeite heeft u met uzelf aankleden?

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We zijn geïnteresseerd in hoe u deze week omgaat met de gevolgen van uw letsel(s) of aandoening(en). We willen graag weten of u hierdoor problemen ondervindt in uw dagelijkse bezigheden.

Graag elke vraag beantwoorden door het best passende antwoord aan te kruisen. Beantwoord alstublieft alle vragen, ook de vragen die ogenschijnlijk niet van toepassing zijn op uw letsel(s) of aandoening(en).

De volgende vragen hebben betrekking op hoeveel moeite u deze week heeft met dagelijkse activiteiten als gevolg van uw letsel(s) of aandoening(en).

Appendix

Appendix 1: The Dutch version of the Short Musculoskeletal Function

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12 Hoeveel moeite heeft u met lopen?

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13 Hoeveel moeite heeft u met het in beweging komen nadat u heeft gezeten of gelegen?

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14 Hoeveel moeite heeft u met het zelfstandig de deur uit gaan?

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15 Hoeveel moeite heeft u met autorijden?

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16 Hoeveel moeite heeft u met het zelfstandig naar het toilet gaan?

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17 Hoeveel moeite heeft u met het gebruiken van knoppen of hendels (bijvoorbeeld het openen van _{deuren of het open draaien van autoramen)?}

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18 Hoeveel moeite heeft u met schrijven of typen?

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19 Hoeveel moeite heeft u met het draaien om uw as?

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20 Hoeveel moeite heeft u met het uitvoeren van uw gebruikelijke lichamelijke recreatieve _{activiteiten, zoals fietsen, hardlopen of wandelen?}

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21 Hoeveel moeite heeft u met het uitvoeren van uw gebruikelijke vrijetijdsbesteding, zoals hobby’s, _{handwerken, tuinieren, kaarten of uitgaan met vrienden?}

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22 Hoeveel moeite heeft u met seksuele activiteiten?

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23 Hoeveel moeite heeft u met het verrichten van lichte huishoudelijke activiteiten of_{tuinwerkzaamheden, zoals afstoffen, afwassen of planten water geven?}

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24 Hoeveel moeite heeft u met het verrichten van zware huishoudelijke activiteiten of_{tuinwerkzaamheden, zoals vloeren dweilen, stofzuigen of grasmaaien?}

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25 Hoeveel moeite heeft u met het uitvoeren van uw dagelijkse werk, zoals een betaalde baan, _{huishouden of vrijwilligerswerk?}

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26 Hoe vaak loopt u mank?

Nooit Zelden Soms Meestal Altijd

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27 Hoe vaak vermijdt u gebruik van uw pijnlijke ledematen of rug?

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28 Hoe vaak zit uw knie op slot of gaat u door uw knie?

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29 Hoe vaak heeft u concentratieproblemen?

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30 Hoe vaak beïnvloedt het te veel doen op een dag uw bezigheden van de volgende dag?

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31 Hoe vaak gedraagt u zich geïrriteerd tegenover mensen om u heen (bijvoorbeeld mensen afsnauwen, kortaf reageren of snel bekritiseren)?

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32 Hoe vaak bent u moe?

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33 Hoe vaak voelt u zich lichamelijk beperkt?

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34 Hoe vaak voelt u zich boos of gefrustreerd vanwege uw letsel(s) of aandoening(en)?

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De volgende vragen informeren naar hoe vaak u deze week problemen ervaart, die veroorzaakt worden door uw letsel(s) of aandoening(en).

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35 In welke mate wordt u gehinderd door problemen bij het gebruik van uw armen, handen of benen?

Geen hinder Geringe hinder Matige hinder Veel hinder Extreem veel hinder

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36 In welke mate wordt u gehinderd door rugproblemen?

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37 In welke mate wordt u gehinderd door problemen tijdens werkzaamheden rondom uw huis?

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38 In welke mate wordt u gehinderd door problemen met douchen of in bad gaan, aankleden, naar het toilet gaan of andere persoonlijke verzorging?

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39 In welke mate wordt u gehinderd door problemen met slapen en rusten?

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40 In welke mate wordt u gehinderd door problemen bij vrijetijdsbesteding en recreatieve _{activiteiten?}

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41 In welke mate wordt u gehinderd door problemen met uw vrienden, familie of andere belangrijke _{mensen in uw leven?}

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42 In welke mate wordt u gehinderd door problemen met nadenken, concentreren of onthouden?

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43 In welke mate wordt u gehinderd door problemen met aanpassen aan of omgaan met uw _{letsel(s) of aandoening(en)?}

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44 In welke mate wordt u gehinderd door problemen met het doen van uw dagelijkse werk?

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45 In welke mate wordt u gehinderd door problemen met het afhankelijk voelen van anderen?

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46 In welke mate wordt u gehinderd door problemen met stijfheid en pijn?

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De volgende vragen hebben betrekking op in welke mate u deze week gehinderd wordt door problemen vanwege uw letsel(s) of aandoening(en).

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