Methods
						
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							Study design:Present key elements of study design early in the paper
						
                        
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							Settings: Describe the setting, locations, and relevant dates, including periods of recruitment, exposure, follow-up, and data collection
						
                        
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							Participants: Give the eligibility criteria, and the sources and methods of selection of participants. Explain how the study size was arrived at 
						
                        
                        
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							Variables: Clearly define all outcomes, exposures, predictors, potential confounders, and effect modifiers. Give diagnostic criteria, if applicable
						
                        
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							Statistical methods:Describe all statistical methods, including descriptive and inferential statistics