Table 3 Overview of challenges encountered most frequently in evidence reviews
Characteristics of the PtDA | Challenges related to available evidence |
|---|---|
Related to treatment alternatives | |
Very different treatment alternatives being compared (Extended) do-nothing compared to active treatments | No directly comparative evidence available: lack of evidence for one/some alternatives but comparative evidence for others Different absolute/relative estimates from heterogeneous reviews/studies Network meta-analysis not considered helpful if effect estimates different compared those of directly comparative evidence |
Established treatments compared to innovations | Older versus newer evidence, absolute numbers differ: interpretation/transferability to current setting difficult Validity of estimates from older studies questionable |
Treatments offered by competing clinical entities (e.g., cardio-surgeons vs. cardiologists) Specific clinical expertise with certain alternatives greater than with others (e.g., laparoscopic vs. open surgery) | Intense but productive discussions with clinicians on best available evidence/evidence interpretation Available evidence does not always seem to well reflect current clinical practice or clinical expertise at UKSH |
Related to target population, subgroups | |
Focus on e.g., elderly patients, children Effect modification/subgroups identified in evidence reviews | Transferability of results from evidence reviews to target group difficult, Support of clinicians needed to interpret evidence and its relevance for target group Need to provide relevant information for subgroups in the PtDA, e.g., for patients with diabetes No separate searches of additional evidence for identified subgroups were usually conducted |
Related to outcomes | |
Decision on framing of outcomes (e.g., mortality versus survival) Specific outcomes (effectiveness/harms) considered very important by patients or physicians | Outcomes reported in the evidence (mortality) were framed differently in the evidence summarization/PtDA (e.g., as survival) to provide most appropriate information to patients in specific situations Second/third round searches for evidence were conducted to fill data gaps |