Four articles have recently been published on a study using the COPM as a measure of effectiveness in a community occupational therapy program for people with Parkinson’s disease and their caregivers. The study is featured here on our news page because it identifies an interesting dilemma in using the COPM in research. The study found significant but modest differences in COPM Performance and Satisfaction scores between treatment and control groups after an average of 8 OT sessions totaling 6½ hours. The authors note, however, that only 67% of the problems raised on the initial COPM were addressed in therapy. The baseline COPM was performed by research staff, and the results passed on to the program therapists. The program therapists then conducted their own evaluations (presumably not using the COPM), and set treatment goals based on their own findings. Thus the net effect is that the program was evaluated on the basis of change in some problems that were not addressed.
While it is methodologically beneficial that assessors be blinded to group designation, it is a significant flaw in the evaluation of this program that the major criterion for effectiveness could well be an issue that was not addressed in the program. There may be other ways to address the issue of rater bias, for example:
- Have treating therapists conduct COPM assessments prior to group allocation;
- Ask therapists to use COPM results as the basis of their initial goal-setting;
- Stipulate a set of goals a priori for the program …
We invite readers to send in addition thoughts and suggestions.
- methodology (Sturkenboom et al., 2013; http://www.ncbi.nlm.nih.gov/pubmed/23374761);
- pilot study (n = 40; Sturkenboom et al., 2012; http://www.ncbi.nlm.nih.gov/pubmed/22811447);
- full trial (n = 191; Sturkenboom et al., 2014; http://www.ncbi.nlm.nih.gov/pubmed/24726066);
- commentary (Saint-Hilaire, Lancet, 2014).