Background: Health technology assessment (HTA) plays an important role in reimbursement decision-making in many countries, but recommendations vary widely throughout jurisdictions, even for the same drug. This variation may be due to differences in the weighing of evidence or differences in the processes or procedures, which are known as HTA practices. Objective: To provide insight into the effects of differences in practices on interpretation of intercountry differences in HTA recommendations for conditionally approved drugs. Methods: HTA recommendations for conditionally approved drugs (N = 27) up until June 2017 from England/Wales, France, Germany, the Netherlands, and Scotland were included. Recommendations and practice characteristics were extracted from these five jurisdictions and this data was validated. The effect of nonsubmissions, resubmissions, and reassessments; costeffectiveness assessments; and price negotiations on changes in the percentage of negative recommendations and the interpretation of intercountry differences in HTA outcomes were analyzed using Fisher exact tests. Results: The inclusion of cost-effectiveness assessments led to significant increases in the proportion of negative recommendations in England/Wales (from 4% to 50%, P,.01) and Scotland (from 21% to 71%, P,.01). The subsequent inclusion of price negotiations led to significant reductions in the proportion of negative recommendations in England/ Wales (from 50% to 14%, P,.01), France (from 31% to 3%, P=.012), and Germany (from 34% to 0%, P,.01). Results indicated that the inclusion of nonsubmissions and resubmissions might affect Scottish negative HTA recommendations (from 7% to 21%), but this effect was not significant. No significant effects were observed in the Netherlands, possibly owing to sample size. Conclusion: Variations in HTA practices between international jurisdictions can have a substantial and significant impact on conclusions about recommendations by HTA bodies, as exemplified in this cohort of conditionally approved products. Studies comparing international HTA recommendations should carefully consider possible practice variations between jurisdictions.