An evaluation study, assessing the pedagogical and instructional design (e-pedagogy) effectiveness of online continuing professional education (CPE) courses offered by a large Australasian CPE provider to health care professionals (HCPs). The study used a naturalistic theory approach in conjunction with a multilevel evaluation to examine the impact of Web-based learning on over 300 HCPs. Several evaluative criteria (participant satisfaction, learning achievement, self-reported practice performance change and e-pedagogical courseware characteristics) were assessed by various qualitative and quantitative data collection methods. The evaluation revealed that learning online was an effective means for increasing CPE knowledge (p < 0.05) and improving self-reported practice performance change (p < 0.05). Additionally the study revealed that of the 42 courses examined, those which included a pedagogically scaffolded clinical or diagnostic learning support tool (57 per cent) resulted in an increased self-reported practice performance change compared with those courses which did not include the scaffolded support tool (Z[subscript obs] 3.757). Participants were very satisfied with the self-paced instruction, timing of both the facilitator and server-generated course comments and the amount of learning content which could be undertaken in a learning sitting.