In patients with chronic obstructive pulmonary disease (COPD), the Late Life Disability Instrument (LLDI) demonstrated test-retest reliability, internal consistency, and construct and face validity. A cross-sectional study with a test-retest component was conducted in Canada and results of the analysis were published in CHEST.1
Recognizing that participation in life roles is not routinely assessed in patients with COPD, investigators sought to determine the measurement properties (ie, test-retest reliability and measurement error between face-to-face and phone administrations, internal consistency, face validity, construct validity, and floor and ceiling effects) of the LLDI in this patient population. The current study compared LLDI scores with scores on measures of theoretically related constructs and between groups, according to symptom severity, prognosis, and frailty.
All of the study participants completed the LLDI, as well as measures of physical function, anxiety and depression, and quality of life during 1 testing session. Additionally, a subsample of participants completed the LLDI once again within 1 week following the initial administration, over the telephone. All of these individuals needed to have been clinically stable (ie, to have experienced no COPD exacerbations) during the time interval between the LLDI administrations.
The LLDI is a 16-item self-report interviewer-administered questionnaire that comprises 2 dimensions of participation, which is measured on 2 separate scales: (1) frequency of performance of major life roles (“very often” to “never” performed) and (2) limitations in perceived ability to perform major life roles (“not at all” to “completely” limited).2
All of the consecutive eligible participants were recruited between February 2018 and March 2020 from respirology clinics and upon admission to pulmonary rehabilitation programs at West Park Healthcare Centre, located in Toronto, Ontario, Canada, and the Firestone Institute for Respiratory Health, St. Joseph’s Healthcare, located in Hamilton, Ontario, Canada. To qualify for enrollment, the adult participants needed to have a primary respiratory diagnosis of COPD, a minimum 10-pack-per-year history of smoking, and to be living in the community (ie, not institutionalized).
A total of 96 older adults with COPD participated in the study. The mean age of the participants was 68.7±8.1 years. Overall, the majority of the participants had severe to very severe COPD. The mean LLDI frequency (LLDI-F) score was 47.0±5.1 points and the mean LLDI limitation (LLDI-L) score was 58.6±9.6 points.
Results demonstrated that the LLDI-F and LLDI-L domains of the LLDI had excellent test-retest reliability, based on 2-way random effect intraclass correlation coefficient (ICC2,1) and absolute standard error of measurement (SEM) values, as follows: ICC2,1 0.90 and SEM 1.74 points for the LLDI-F vs ICC2,1 0.90 and SEM 3.16 points for the LLDI-L.
Both the LLDI-F and the LLDI-L domains had fair correlations with physical function, depression, and quality of life (r=0.38-0.59). The relationship with anxiety was poor for the LLDI-F domain (r=-0.21) and fair for the LLDL-L domain (r=-0.45). Both of the domains distinguished between individuals with different symptom severity, prognosis, and frailty (P ≤.026). Regarding face validity, most of the participants agreed that the LLDI measures participation (79%), that the items in the questionnaire were relevant to them (81%), and that the questions in the LLDI are easy to understand (94%).
The investigators concluded that future studies are warranted to evaluate responsiveness of the LLDI measure to change over time. Once the responsiveness of the measure has been determined, the next step will be to assess the effectiveness of the interventions for increasing participation in individuals with COPD.
1. O’Hoski S, Kuspinar A, Richardson J, et al. A tool to assess participation in people with COPD: validation of the Late Life Disability Instrument. CHEST. Published online August 31, 2020. doi:10.1016/j.chest.2020.08.2079
2. Jette AM, Haley SM, Kooyoomjian JT. Late-Life FDI Manual. Boston University Sargent College of Health and Rehabilitation Sciences. Roybal Center for the Enhancement of Late-Life Function; 2002.