Author's response to reviews Title:A cross-sectional, population-based study measuring comorbidity among people living with HIV in Ontario Authors:

24. Methods: I would suggest omitting the word ‘burden’ from the second last sentence. We have changed burden to prevalence in this sentence. 25. In addition, separating mental health morbidity from physical health morbidity adds little to the paper. We respectfully disagree with the reviewer on this point. The prevalence of mental health conditions is incredibly high in people with HIV, a reality with a significant impact on their ability to access and sustain care and therapy. In fact, the adverse role of mental health conditions on the care and treatment of other conditions, like diabetes, is increasingly understood. We believe it’s important to leave mental health as a separate entity and feel doing so doesn’t hamper the readability of the paper. We hope the reviewer and editor agree. 26. Results: Second sentence – ‘Burden was especially high for...’ – isn’t this sentence simply saying that the prevalence of mental illness, hypertension and asthma was especially high among the HIV cohort? The remainder of the paragraph returns to using prevalence. We have changed burden to prevalence in this sentence on page 9. 27. Conclusion: Including co-morbidity and multimorbidity and then adding ‘burden’ complicates what should be a relative straight-forward narrative here. It makes much more sense without the word ‘burden’. We have made the suggested changes to these sentences. 28.Overall Overall, interesting paper with new information and should be published. I would suggest some serious editing of the document, reduce the length (repetitive in places) and improve the flow/style of the writing. I would seek to integrate Introduction, Results and Discussion in a more seamless fashion. Improve the consistency of the terms used – co-morbidity and multimorbidity – it might be better to concentrate on co-morbidity only, using HIV as the index case. I would have mental illness as a morbidity like the other nine chronic conditions. I would omit the term ‘burden’ and use prevalence instead. We thank the reviewer for his/her suggestions and hope the detailed changes improve the readability of the manuscript. Additional Editorial Request: 29.) Please include your figure legends separately at the end of your manuscript file rather than as part of your figures files as described in our guidelines: (http://www.biomedcentral.com/bmcpublichealth/authors/instructions/researcharticle#pr eparing-figures). We have included only the captions in the article and have uploaded the figures as a separate file.