The objective of this work was to assess the performance of the newly developed Health-Related Productivity Questionniare-Diary (HRPQ-D). Patients completed the HRPQ-D daily for 1-week periods during weeks 1, 2, 4, and 8 of a clinical trial for infectious mononucleosis. Productivity data were collected on a daily basis in terms of absenteeism, presenteeism, and combined lost productivity for three work venues (work outside home, housework, and classes/homework). These were then correlated with patient symptom scores. Symptom scores were positively correlated with lost work hours because of absenteeism and combined lost productivity scores. However, negative correlations were observed between symptom scores and the lost work hours due to presenteeism. The HRPQ-D demonstrated good construct validity, making it a useful tool for determining productivity levels across different work venues within clinical trial or survey research applications.