Abstract
Purpose :
Low vision rehabilitation (LVR) is goal-directed with LVR goals defined by the patient and/or therapist. The Activity Inventory (AI) item bank includes 50 commonly identified vision-dependent daily living, social interaction, and recreation goals. Patients rate the importance of each goal and the difficulty only of the goals that are important to them. When using the AI as a LVR outcome measure it is important to know if measured outcomes are influenced by the agreement of patient-identified AI goals with the activity goals included in the patient’s plan of care (POC) by the therapist.
Methods :
The AI was administered to 100 low vision patients before (Pre) and after (Post) LVR provided by 10 occupational therapists (OT). The OT identified which of the AI goals rated by the patient to be at least “slightly important” and at least “slightly difficult” were included in the patient’s POC. Outcome measures were estimated by Rasch analysis of AI goal difficulty ratings, with goals having a Pre-LVR rating of “not important” or “no difficulty” scored as missing data for both Pre-LVR and Post-LVR analyses. AI item measures and rating category thresholds were anchored to previously calibrated values. Change in visual ability (difference between Post-LVR and Pre-LVR person measures) was estimated for each patient. The number of AI goals rated as both important and difficult and the percent of those goals that were included in the POC also were recorded for each patient.
Results :
The measured change in visual ability increased in proportion to the percent of AI goals included in the POC (p<0.01). As shown in Figure 1, the measured change in visual ability decreased exponentially with increases in the number of patient-identified AI goals. The percent of patient-identified AI goals included in the POC decreased exponentially with increases in the number of patient-identified AI goals.
Conclusions :
The magnitude of change in overall visual ability measures corresponds to the average change in functional ability across goals. As the number of AI goals increases, the average change in functional ability decreases asymptotically. The probability that goals in the POC match the patient’s AI goals also decreases with increases in the number of patient-identified AI goals, indicating potential limitations on the number of goals that practically can be addressed.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.