Journal Article

Validity and responsiveness of the Daily- and Clinical visit-PROactive Physical Activity in COPD (D-PPAC and C-PPAC) instruments

MacNee, Bill, Frei, Anja, Hopkinson, Nick S, Puhan, Milo A, Ivanoff, Nathalie, Dobbels, Fabienne, Erzen, Damijen, Foundation, Netherlands Asthma, Louvaris, Zafeiris, Demeyer, Heleen, Erzen, Damijan, Karlsson, Niklas, Tabberer, Maggie, de Jong, Corina, Boer, Pim de, Polkey, Michael I, Serra, Ignasi, Vogiatzis, Ioannis, Molen, Thys van der, Kamel, Nadia, Jong, Corina De, Garcia-Aymerich, Judith, Hopkinson, Nicholas S, Glendenning, Alastair, Montaccini, Roberta, Kulich, Karoly, Scuri, Mario, Jarrod, Ian, Gimeno-Santos, Elena, Rabinovich, Roberto A, Troosters, Thierry, Corriol-Rohou, Solange, Allinder, Matthew, McLoughlin, Katrina

2021

Overview

BackgroundThe Daily-PROactive and Clinical visit-PROactive Physical Activity (D-PPAC and C-PPAC) instruments in chronic obstructive pulmonary disease (COPD) combines questionnaire with activity monitor data to measure patients’ experience of physical activity. Their amount, difficulty and total scores range from 0 (worst) to 100 (best) but require further psychometric evaluation.ObjectiveTo test reliability, validity and responsiveness, and to define minimal important difference (MID), of the D-PPAC and C-PPAC instruments, in a large population of patients with stable COPD from diverse severities, settings and countries.MethodsWe used data from seven randomised controlled trials to evaluate D-PPAC and C-PPAC internal consistency and construct validity by sex, age groups, COPD severity, country and language as well as responsiveness to interventions, ability to detect change and MID.ResultsWe included 1324 patients (mean (SD) age 66 (8) years, forced expiratory volume in 1 s 55 (17)% predicted). Scores covered almost the full range from 0 to 100, showed strong internal consistency after stratification and correlated as a priori hypothesised with dyspnoea, health-related quality of life and exercise capacity. Difficulty scores improved after pharmacological treatment and pulmonary rehabilitation, while amount scores improved after behavioural physical activity interventions. All scores were responsive to changes in self-reported physical activity experience (both worsening and improvement) and to the occurrence of COPD exacerbations during follow-up. The MID was estimated to 6 for amount and difficulty scores and 4 for total score.ConclusionsThe D-PPAC and C-PPAC instruments are reliable and valid across diverse COPD populations and responsive to pharmacological and non-pharmacological interventions and changes in clinically relevant variables.

• Publisher: BMJ Publishing Group Ltd and British Thoracic Society,BMJ Publishing Group LTD,BMJ Publishing Group
• Subject: Chronic Obstructive Pulmonary Disease / COPD epidemiology / Exercise / Exercise - physiology / Exercise Therapy - methods / Exercise Tolerance - physiology / Follow-Up Studies / Forced Expiratory Volume / Humans / Intervention / Lung diseases / Non-pharmacological intervention / Patients / Physical fitness / Prospective Studies / Psychometrics - methods / Pulmonary Disease, Chronic Obstructive - physiopathology / Pulmonary Disease, Chronic Obstructive - rehabilitation / Quality of Life / Questionnaires / Spirometry / Statistical analysis / Surveys and Questionnaires / Validity