The de Morton mobility index is a feasible and valid mobility assessment tool in hospitalized patients with an acute exacerbation of chronic obstructive pulmonary disease

Abstract

There is no accepted standard for measuring mobility in hospitalized patients with an acute exacerbation of chronic obstructive pulmonary disease (AECOPD). The objective of this study was to assess convergent, discriminant, and known-group validity and floor/ceiling effects of the de Morton Mobility Index (DEMMI) in hospitalized patients with AECOPD. Individuals with AECOPD ( n = 22) admitted to an acute care hospital medical ward were recruited. Data on the DEMMI, gait speed, daytime energy expenditure, step counts, 6-minute walk distance (6MWD), dyspnea, respiratory and heart rates, quality of life, and oxygen supplementation were collected on day 3 of admission. The DEMMI demonstrated convergent validity with the 6MWD and gait velocity measures (Spearman’s ρ 0.69 and 0.61, respectively; p < 0.003) but not with measures of physical activity or respiratory impairment. Discriminant validity was present, with no correlation between the DEMMI and quality of life and resting heart rate. Known-group validity (gait aids vs. no gait aids) was demonstrated ( p = 0.009). There was no floor effect but there was evidence of a possible ceiling effect (14% of participants received a perfect score). The DEMMI is feasible and showed moderate to strong validity with measures of observed physical function in hospitalized patients with AECOPD.

Performance-based outcome measures to assess functionality in hospitalised patients with COPD exacerbations: a systematic review of the measurement properties

“…C amp et al . [ 34 ] assessed the construct validity of the DEMMI; specifically, convergent validity, known-group validity and discriminative validity. The convergent validity had a hypothesis of correlation of 0.60 with other functional measurements for the lower limb and we found two results in line with the hypotheses (6-min walk distance (6MWD): rho=0.69 (p=0.0006); gait velocity: rho=0.61 (p=0.0028)).…”

“…Functionality categories were classified as the body function category, which included "functions of the cardiovascular and respiratory systems" and "neuromusculoskeletal and movement-related functions", and the activities category, which included "mobility" (table S1). Outcome measures were divided into eight functionality outcomes, as follows: 1) lower limb function and exercise tolerance using the 6-min stepper test (6MST) [27]; 2) peripheral muscle strength using handgrip strength (HGS) [28]; 3) respiratory muscle strength using maximal inspiratory pressure (MIP) [29,30]; 4) upper limb function and exercise tolerance using the 6-min pegboard and ring test (6PBRT) [31,32]; 5) balance using the Berg balance scale (BBS) [33]; 6) mobility using the de Morton mobility index (DEMMI) [34]; 7) walking capacity using 4-m gait speed (4MGS) [35]; and 8) walking capacity and exercise tolerance using the ISWT [36] and 6MWT [37][38][39]. The characteristics of the outcome measures are presented in table S2.…”

“…Mobility DEMMI: one study assessed the validity of the DEMMI [34]. CAMP et al [34] assessed the construct validity of the DEMMI; specifically, convergent validity, known-group validity and discriminative validity.…”

Development of a performance-based toolkit of the treatable traits of functioning in hospitalised patients with exacerbation of COPD: a survey-based study protocol

“…Although some performance-based measures have been developed to assess functioning of hospitalised patients, such as Physical Function in Intensive Care measure (PFIT) [ 16 ], the de Morton Mobility Index (DEMMI) [ 17 ] and the Short Physical Performance Balance (SPPB) test [ 18 ], these measures do not consider the specific demands of hospitalised patients with ECOPD.…”

Acute exacerbations of chronic respiratory disease: Progress and opportunities

“…Many, but not all, of these papers pertain to patients with acute exacerbations of chronic obstructive pulmonary disease, perhaps reflective of the ongoing challenges that acute healthcare providers face to optimally manage this patient group. Read the whole collection and you will gain valuable insights spanning a diverse range of study designs, exploration of issues via quantitative and qualitative methodologies, focused reports of physiotherapeutic practices from different countries across the globe, 5,6 updates regarding instrument validation (De Morton Mobility Index) for use in the acute hospital environment, 7 evaluations of biomarker utility 8 and clinical stratification 9 during acute exacerbations of interstitial lung disease and exploration of issues affecting rates of pulmonary rehabilitation uptake in the period after acute respiratory exacerbations. 10,11 Suffice to say, whether you are a clinician, researcher, healthcare policy maker or an individual affected by chronic respiratory disease, we hope you will find something that will appeal to your interests within this special collection.…”