Background: Problems related to performance of activities of daily living (ADL) tasks is associated with chronic conditions stressing a need to develop and evaluate intervention programmes addressing such problems. Guided by the United Kingdom Medical Research Council’s (MRC) guidance on how to develop and evaluate complex interventions, the first version of the occupational therapy program (ABLE 1.0) was developed, aiming at enhancing ADL ability among persons with chronic conditions. ABLE incorporates knowledge based on existing evidence, clinical expertise of occupational therapists, and clients’ experiences and needs. ABLE is a structured eight-week, generic, homebased, adaptational program, including five to eight individualised sessions, developed to be delivered in the client’s home as part of community-based rehabilitation services. Following development of the programme, a feasibility study was conducted, showing that ABLE 1.0 was feasible in terms of content and delivery with minor adjustments to the intervention manual and recruitment procedures. Hence, pilot testing of the remaining uncertainties was recommended before proceeding to the evaluation phase. The aim of this doctoral thesis was to evaluate the remaining feasibility aspects prior to a randomised controlled trial (RCT), including minor revision of ABLE 1.0, and to conduct effectiveness and process evaluation of ABLE 2.0.
Methods: The MRC framework for developing and evaluating complex interventions was applied. Revision of ABLE 1.0 included conduction of a cognitive debriefing including n=5 occupational therapists to identify any aspect of the ABLE manual leading to confusion or misunderstanding. Further, relevant updates of theoretical models incorporated in ABLE 1.0 were implemented.
The pilot study was designed as a two-armed parallel RCT, planning a recruitment strategy including 20 persons with one or more chronic conditions and experiencing problems performing ADL tasks. The pilot study period was scheduled from December 2019 to April 2020. The following progression criteria were used to determine if a future full-scale RCT was feasible: (i) recruitment (50% met the eligibility criteria) and retention (80%), (ii) randomisation (80% accepted randomisation, procedure was executed as planned), (iii) adherence to programme (100% followed the treatment protocol), (iv) outcome measurements (80% of the participants delivered relevantly and fully answered questionnaires), and (v) usual occupational therapy (extraction of needed information was successful).
The subsequent effectiveness evaluation was designed as a RCT with blinded assessors and investigators. Home-dwelling persons with chronic conditions experiencing ADL task performance problems were randomly allocated to ABLE 2.0 or usual occupational therapy. Data were collected at baseline (week 0), post intervention (week 10) and at follow-up (week 26). Coprimary outcomes were self-reported ADL ability (ADL-Interview (ADL-I) performance) and observed ADL motor ability (Assessment of Motor and Process Skills (AMPS)) at primary endpoint (week 10). Secondary outcomes were self-reported ADL ability (ADL-I performance), observed ADL motor ability (AMPS) at secondary endpoint (week 26) and perceived satisfaction with ADL ability (ADL-I satisfaction); and observed ADL process ability (AMPS) at primary and secondary endpoint. Explorative outcomes were occupational balance (Occupational Balance Questionnaire); perceived change (Client Weighted Problems Questionnaire) and general health (first question of the MOS 36-item Short Form Survey Instrument) at primary and secondary endpoint. All outcomes were analysed using the principles of Intention-To-Treat (ITT) analyses followed by sensitivity analyses in terms of Per Protocol (PP) analyses, applying analysis of covariance (ANCOVA) with time by programme as repeated measures. ADL-I at baseline was included as covariate.
In the process evaluation a realist evaluation approach was applied. A programme theory (ABLE 2.0 initial programme theory) was constructed expressing how contexts (C) and mechanisms (M) in the intervention programme were hypothesised to lead to certain outcomes (O), in so-called CMO configurations. The process evaluation was based on qualitative interview data from a sub-group of clients (n=8) and the occupational therapists delivering the programme (n=3), supplied by quantitative data from registration forms, filled in by clients receiving (n=38) and OTs delivering (n=3) ABLE 2.0.
Results: Based on data from the cognitive debriefing and updated theory the manual was revised resulting in ABLE 2.0. Due to the Covid-19 pandemic the pilot study was interrupted in March 2020, resulting in limited but sufficient data to answer most of the study questions. (i) Eighteen of 37 eligible persons (48.6%) were recruited; of those treated (n = 6), all remained in the programme (100%); (ii) 18 accepted randomisation (100%), and procedure was effective; (iii) ABLE was delivered with adherence (100%); (iv) 92.3–100% of the participants gave relevant and complete answers in two of three questionnaires; and (v) the needed information on usual occupational therapy was extractable in seven of nine aspects.
In the effectiveness evaluation ITT analysis of primary outcomes identified no statistically significant nor clinically relevant difference between group mean changes on self-reported, i.e. ADL-I performance (-0.16; 95 % CI: - 0.38 to 0.06) and observed ADL ability, i.e. AMPS ADL motor ability (-0.1; 95 % CI: -0.3 to 0.1) from baseline to week 10. However, at the secondary endpoint (week 26) a statistically significant and clinically relevant difference was found in AMPS ADL motor ability (LS mean change = -0.3; 95% CI = -0.5 to -0.1) between groups. This was confirmed in the sensitivity analysis (LS mean change = -0.4; 95% CI = -0.7 to -0.1).
The process evaluation overall confirmed the initial programme theory, adding information on core mechanisms associated with the positive effects of the ABLE 2.0. These included active involvement of the client in the problem-solving process, a collaborative working relationship, mutual confidence, and a consultative occupation-based process using adaptational strategies. Several contextual factors were required to activate the desired mechanisms in terms of supportive management, referral procedures encouraging the problem-solving process, delivery in the client’s home, skilled OTs, and clients feeling ready for making changes.
Conclusions: Based on the results it was concluded that the ABLE 2.0 was effective in improving observed ADL motor ability, reflecting a decreased level of effort in terms of clumsiness, physical effort, and fatigue among persons with chronic conditions. Sustainability of the improvements in ADL motor ability was obtained based on delivering the individualised systematic problem-solving process in the home of the client and by using adaptational strategies. Finally, because baseline ADL ability was identified as the only area were persons who benefitted differed from those who did not, and the ABLE 2.0 otherwise was effective across age, gender and diagnoses, the idea of developing a generic programme was supported. Based on the conclusions it is recommended to proceed to planning of research activities aiming at implementing the ABLE intervention programme in clinical communitybased rehabilitation settings.