Functional capacity, physical activity and muscle strength assessment of individuals with non-small cell lung cancer: a systematic review of instruments and their measurement properties

BACKGROUND: The measurement properties of instruments used to assess functional capacity, physical activity and muscle strength in participants with non-small cell lung cancer (NSCLC) have not been systematically reviewed. METHOD: Objectives: To identify outcome measures used to assess these outcomes in participants with NSCLC; and to evaluate, synthesise and compare the measurement properties of the outcome measures identified. Data Sources: A systematic review of articles using electronic databases MEDLINE (1950–2012), CINAHL (1982–2012), EMBASE (1980–2012), Cochrane Library (2012), Expanded Academic ASAP (1994–2012), Health Collection Informit (1995–2012) and PEDRO (1999–2012). Additional studies were identified by searching personal files and cross referencing. Eligibility Criteria for Study Selection: Search one: studies which assessed functional capacity, physical activity or muscle strength in participants with NSCLC using non-laboratory objective tests were included. Search two: studies which evaluated a measurement property (inter- or intra-rater reliability; measurement error; criterion or construct validity; or responsiveness) in NSCLC for one of the outcome measures identified in search one. Studies published in English from 1980 were eligible. Data Extraction and Methodological Quality Assessment: data collection form was developed and data extracted. Methodological quality of studies was assessed by two independent reviewers using the 4-point COSMIN checklist. RESULTS: Thirteen outcome measures were identified. Thirty-one studies evaluating measurement properties of the outcome measures in participants with NSCLC were included. Functional capacity was assessed using the six- and twelve-minute walk tests; incremental- and endurance-shuttle walk tests; and the stair-climbing test. Criterion validity for three of these measures was established in NSCLC but not the reliability or responsiveness. Physical activity was measured using accelerometers and pedometers. Only the construct validity for accelerometers and pedometers was reported. Muscle strength was measured using hand-held dynamometry, hand-grip dynamometry, manual muscle test, one-repetition maximum and the chair-stand test, however only two studies reported reliability and measurement error and one study reported construct validity. CONCLUSION: Currently there is a gap in the literature regarding the measurement properties of commonly used outcome measures in NSCLC participants, particularly reliability, measurement error and responsiveness. Further research needs to be conducted to determine the most suitable outcome measures for use in trials involving NSCLC participants.