How to Conduct a Medical Research Paper
The foundation of any successful medical research paper begins with developing a clear, focused research question using the PICO framework (Population, Intervention, Comparator, Outcome), followed by a rigorous protocol that serves as your roadmap through study design, data collection, analysis, and dissemination. 1
Phase 1: Formulating the Research Question
Apply the FINER Criteria
Your research question must be Feasible, Interesting, Novel, Ethical, and Relevant (FINER) to ensure it generates clinically impactful knowledge. 1, 2 This prevents wasting resources on questions of marginal interest or those that ignore important existing work. 1
Structure Using PICO Framework
- Population: Define your target patient population with specific characteristics 1, 3
- Intervention/Exposure: Specify the intervention or exposure being studied 1, 3
- Comparator: Identify what you're comparing against (control, standard care, placebo) 1, 3
- Outcome: Define outcome measures as precisely as if conducting an original study yourself 1
- Timeframe: Establish the duration reasonable for outcome development 1
Conduct Comprehensive Literature Review
Perform an extensive literature search to understand what is already known, identify gaps in current evidence, and justify why a new study is needed. 1 Search ClinicalTrials.gov to avoid unnecessary duplication and learn from similar ongoing studies. 1
Phase 2: Protocol Development
Create a Detailed Written Protocol
A well-developed protocol is the single most critical determinant of overall study quality and potential bias. 1, 3 The protocol serves as your complete roadmap and should include: 1, 3
- Study rationale and objectives: Classify as descriptive and/or analytical 3
- Study design: Clearly identify whether RCT, prospective cohort, case-control, cross-sectional, or case series 1
- Eligibility criteria: Detailed inclusion/exclusion criteria 3
- Sample size calculation: Pre-planned with power calculations 3
- Data collection methods: Specify timing and assessment methods for all variables 3
- Statistical analysis plan: Include pre-planned strategies to identify and mitigate bias 3
Register Your Protocol
Register the protocol prospectively in ClinicalTrials.gov or appropriate registry before patient enrollment or data collection begins. 1, 3 This prevents selective publication, protocol changes, and unnecessary research duplication. 1
Adhere to Reporting Standards
Follow established guidelines: 3
- PRISMA-P for systematic reviews and meta-analyses 1
- SPIRIT for clinical trial protocols 3
- ARRIVE for animal research 3
Phase 3: Study Design Selection
Match Design to Question
The study design must be appropriate for the specific question being asked. 1 Consider this hierarchy: 1
- Randomized Controlled Trials (RCTs): Provide maximum-quality evidence on benefits and risks of interventions; use when sufficient preliminary data exists 1
- Prospective Cohort Studies: Preferred for higher-level evidence when RCTs are not feasible 1, 3
- Registries: Essential for assessing real-world use, costs, and effectiveness 1
- Observational Studies: Appropriate when generating hypotheses or preparing ground for RCTs 1
Common Pitfall to Avoid
Do not combine results from observational cohorts and randomized trials in the same analysis, as differences in study design, follow-up duration, and exposure definitions lead to misleading findings. 1
Phase 4: Data Collection and Management
Define All Variables Precisely
Provide a complete list of core variables grouped as: 3
- Baseline characteristics
- Exposures
- Outcomes (primary and secondary, pre-specified before analysis) 3
Describe each variable in detail including timing of collection and assessment methods. 3
Ensure Reproducibility
Test and report: 1
- Observer reproducibility: Inter-observer and intra-observer variability
- Test-retest reproducibility: Using intra-class correlation coefficients (ICC) with 95% CI and Bland-Altman analysis as minimum standards 1
- Never use simple correlations or mean value comparisons for reporting reproducibility 1
Enroll Consecutively
Begin enrolling consecutive patients at study onset to avoid selection bias. 3 Document recruitment strategies to understand potential biases in your target sample. 3
Phase 5: Statistical Analysis
Pre-Specify Analysis Plan
The statistical analysis plan must be developed during protocol creation, not after data collection. 3 Include: 1
- For prognostic studies: Univariable and multivariable analysis (logistic or Cox regression) adjusted for traditional risk factors 1
- For prediction models: Assess discrimination (ROC curve, sensitivity, specificity), calibration (calibration slopes, Hosmer-Lemeshow test), and additional predictive value (C-statistic increment, NRI, IDI) 1
- For heterogeneity assessment: Use I² and Cochran Q statistics with forest plots for visual inspection 1
Collaborate with Statisticians
Engage expert statisticians early for sample size estimation and analysis planning. 1 This collaboration is essential for avoiding fatal methodological flaws. 1
Phase 6: Quality Assessment and Bias Mitigation
Assess Study Quality
Use established tools to assess potential for bias: 1
- Risk of bias assessment tools for included studies
- GRADE or similar frameworks for certainty of evidence 1
Address Ethical Considerations
Obtain appropriate institutional review board or ethics committee approval before study initiation. 3 Include trial registration numbers in all publications. 3
Phase 7: Dissemination
Plan Multi-Directional Dissemination
- Identify target audiences (specialists, clinicians, patients, stakeholders) 1
- Use multiple venues while respecting policies on data reuse 1
- Encourage collaborator participation to amplify dissemination 1
Report Completely and Transparently
Follow reporting guidelines specific to your study design to ensure concise, explicit, and complete reporting. 4 Both positive and negative findings should be published to advance the field. 1
Critical Success Factors
The three most common reasons research fails are: 1
- Poorly defined research question leading to inappropriate study inclusion and substantial heterogeneity 1
- Vague protocol criteria introducing unnecessary subjectivity during screening and data extraction 1
- Inadequate subject matter expertise in translating the hypothesis into an executable protocol 1
Avoid these pitfalls by investing substantial time upfront in question formulation and protocol development before collecting any data. 1