OBJECTIVES: To investigate whether electronic memory aids and IVR verbal numeric scales improve the quality of data collection methods. To evaluate whether perceptions of clinical change reported directly by the patient is enhanced by the use of a novel telephone based interactive voice response system. METHODS: A total of 137 patients from a multi-site, double-blind, placebo controlled study were administered the IVR PGI-I and the Memory Enhanced Retrospective Evaluation of Treatment (MERET) over a 4-week period. Effect sizes using these approaches were determined and compared to determine any differences. In addition, we investigated whether dosage level predicted a more rapid onset of action. RESULTS: At 2 and 4 weeks the point estimates for both IVR PGI-I and MERET were 2.68 and 3.24 (p=.035) and 2.5 and 3.21 (p=.015), respectively. Overall, the effect size for the PGI-I was 0.526 compared to 0.612 for MERET. For the subjects in the higher dose group, there were significant improvements reported by the patient at 1 day for shoulder (p=.008) and back pain (p=.01). Significant differences were also found at day 3 for pain while awake (p=.03), day 5 for Global emotional improvement (p=.03), and day 7 and Global physical improvement (p=.04) at day 7. No other significant differences were found. CONCLUSION: The use of an electronic memory aid produced a 16.3% larger drug-placebo treatment effect size compared to the standard PGI-I. MERET ratings increased the patients' perception on the effectiveness of active drug treatment with minimal influence of the placebo effect. In this study, the higher dose had an earlier onset of efficacy for both physical and emotional symptoms. The daily IVR reporting of this data allowed detection of a rapid onset of action.