Background: Inadequately completed laboratory test request forms contribute to preanalytical errors and limit the advice of pathologists when interpreting laboratory test results. Educating clinicians about this has been proposed by several studies as a strategy to reduce the occurrence. Aim: We aimed to determine the effectiveness of such education on the prevalence of adequately completed laboratory test request forms. Subjects and Methods: This was a quasi‑experimental study conducted at the chemical pathology laboratory of the Lagos University Teaching Hospital, Nigeria. Incoming laboratory request forms were audited for a period of 1 month looking out for eight data variables. Subsequently, intensive clinician education was undertaken via seminars, publications, and orientation programs on 670 clinicians for 6 weeks duration. After that, a repeat audit for the same data variables was conducted for another period of 1 month. A Z‑test of significance for the comparison of independent proportions was conducted for form errors pre‑ and post‑intervention. Results: Error rates for missing variables pre‑ and post‑clinician education were: Name pre = 0 (0%), post = 0 (0%); age pre = 330 (21.6%), post = 28 (1.9%), P < 0.001; gender pre = 64 (4.2%), post = 53 (3.6%), P = 0.37; hospital number pre = 848 (55.6%), post = 524 (35.3%), P < 0.001; clinician name pre = 165 (10.8%), post = 64 (4.3%), P < 0.001; ward/clinic pre = 311 (20.4%), post = 235 (15.8%), P < 0.01; clinical diagnosis pre = 220 (14.4%), post = 33 (2.2%), P < 0.001; specimen type pre = 169 (11.1%), post = 116 (7.8%), P < 0.01, respectively. Conclusion: There was an improvement in the inadequate completion of laboratory request forms after clinicians were educated on proper completion using various interactive media, showing that it is an effective strategy. However, further studies are required to identify which educational strategy is most effective in reducing error rates in laboratory test request forms.