In recent years, the importance of understanding the impact of interventions on an individual's ability to participate in social roles after a stroke event has gained much attention. Comprehensive assessment of treatment effectiveness should include a broader range of outcomes, including social participation. This study attempted to determine the degree to which the assessment of social participation has been included in randomized controlled trials of stroke rehabilitation. An extensive literature search was used to identify all randomized controlled trials from 1968 to 2005. Assessment scales used to evaluate study outcomes were recorded and classified based on the International Classification of Functioning Disability and Health (ICF) framework. Studies citing assessment of more than one ICF component were identified. In total, 1447 outcomes were assessed using 489 measurement scales and were cited in 491 identified trials. Both number of studies and assessment of participation outcomes increased over time. Participation assessments accounted for less than 6% of all measurement citations. Around 56.8% of studies reported multicomponent assessment. Of these, 25% included assessment at the level of ICF Participation. In conclusion, the vast body of work within the areas of impairment and function is a cornerstone for rehabilitation. This is certainly reflected in the recorded measurement citations. Despite increasing awareness and a significant increase in participation assessment, relatively few studies include assessment at this level, thereby limiting our understanding with regard to the impact of rehabilitation interventions on more complex areas of social participation.