Several challenges can impact the quality of evidence:
1. Publication Bias: Studies with positive results are more likely to be published, skewing the available evidence. 2. Heterogeneity: Variability in study designs, populations, and outcomes can make it difficult to synthesize evidence. 3. Data Quality: Poor data quality, including issues with data collection and measurement errors, can compromise evidence quality. 4. Funding and Conflicts of Interest: Studies funded by entities with vested interests may be biased.
