This paper provides a comprehensive review and comparison of instruments used to assess patient-doctor interaction over the past decade. Instruments were identified from papers indexed by MEDLINE from 1986 to 1996 using the medical subject headings 'physician-patient relations', 'physician-patient communication', and 'education, medical', as well as requests for instruments currently in use by colleagues. Each instrument was reviewed under the following categories: name of the instrument; description; number of items; reliability; validity; current use and special notes. Overall, 44 instruments were obtained and reviewed. Of these, 21 were used in only one published study each in the last decade and 15 have never been validated. While most instruments have been shown to be reliable (usually inter-rater reliability), very few instruments have been directly compared with another instrument designed to assess patient-doctor interactions. We suggest that further validation of existing instruments and incorporation of assessment of non-verbal communication between the patient and the doctor are needed.