Using 16,068 articles in Wikipedia's Medicine Wikiproject, we study the relationship between collaboration and quality. We assess whether certain collaborative patterns are associated with information quality in terms of self-evaluated quality and article viewership. We find that the number of contributors has a curvilinear relationship to information quality, more contributors improving quality but only up to a certain point. Other articles that its collaborators work on also influences the quality of an information artifact, creating an interdependent network of artifacts and contributors. Finally, we see evidence of a recursive relationship between information quality and contributor activity, but that this recursive relationship attenuates over time.