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Research Proposal. Data collection Components of the study Baseline – what, where, when and how Follow-up – what, where, when and how Questionnaire, interview, venipuncture, physical measurements, medical record review Develop a figure that depicts data collection for each participant.
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Research Proposal • Data collection • Components of the study • Baseline – what, where, when and how • Follow-up – what, where, when and how • Questionnaire, interview, venipuncture, physical measurements, medical record review • Develop a figure that depicts data collection for each participant.
Surgery Liver Biopsy OR Enrollment (n=50) Bariatric Patients Pre-surgery Full Exam GCRC 4-week Post-OP Full Exam GCRC 12-month Post-OP Full Exam GCRC 3,6,9-month Post-OP Brief Exam GCRC Enroll 600 women Figure 3. Study Components Prenatal Examination GCRC Medical Record Abstraction Delivery Cord Blood Telephone Interview 2 week 3 month 6 month 9 month 6-week Examination GCRC Mother and Child Components 1-year Examination GCRC Mother and Child Components Figure 5.1. Components of the proposed study Research Proposal
Research Proposal • Data collection • Main Exposure and Outcome Variables • Details on what will be collected for these variables • Questionnaires • Developed for this study? • Has it been validated? • Has it been validated in race/ethnic, age, gender? • What language will be used? • If you are studying acculturation how will it impact your study if questionnaires are only available in English • Scale or a score, need to provide information on the range of values, how it is scored and interpreted, what type of variable is the output (continuous, discrete, ordinal, nominal)
Research Proposal • Data collection • Main Exposure and Outcome Variables • Details on what will be collected for these variables • Laboratory assays • Variation • How standardized are the measurements. • Are there different analytical techniques? • Does it matter which one you use? • Batch variation – is this a problem • Biologic variation – is this a problem • Upper and lower bounds • Reliability coefficient, same person different days, same sample different times • Where will the assays be completed. Will samples be stored and measured all at once or will they be sent as acquired.
Research Proposal • Data collection • Main Exposure and Outcome Variables • Details on what will be collected for these variables • Standardized measurements • Blood pressure, ultrasound, MRI • Need a standardized protocol for how you will measure it • Clinical protocol is not good enough • Good starting spot • Need a standardized protocol for how you will read it • Clinical protocol is not good enough • May need repeatability studies for scanning/reading • Blinded
Research Proposal • Data collection • What is the final information that will be obtained • DXA – percent body fat • MRI – visceral adiposity, amount of fat in kg • Carotid ultrasound – intima media thickness • The focus of your study – may be a lot of information available but what is central to your study.
Research Proposal • Data collection • Main Exposure and Outcome Variables • Details on what will be collected for these variables • Case definitions • Define exposure, outcome or study population • Clinical definition – not ideal • Standard criteria • What information are needed to make the diagnosis • How will you get that information: Abstract medical record or measure required variables to obtain all required information • Develop algorithm to define disease - missing data
Research Proposal • Data collection • Confounders -- covariates • Identify potential confounders • Comorbidities • Age, sex, race, SES • Observational study – these can make or break • Less information on measurement of these variables
Research Proposal • Data analysis • For each hypothesis write out your exposure and outcome. • Indicate variable to be used in analysis for both the exposure and outcome. • Continuous, categorical, nominal or ordinal • Power calculation for that hypothesis
Research Proposal • Theoretical model • Exposure Outcome • Covariates – where do they enter in
Microbiome Hepatocyte Metabolism Diet/ Physical Activity Incretin/Satiety Obesity ↕ Visceral Adiposity Insulin Resistance ↕ Impaired Insulin Secretion Diabetes Hepatic Steatosis Figure 4. Aim 1 Conceptual Framework; Proposed etiology of diabetes and hepatic steatosis in morbidly obese patients prior to gastric bypass surgery. Research Proposal
Research Proposal • Problems, Pitfalls and limitations • Keep a running list of problems with your study