As a result of the inclusion criteria used and the time frame of this study, the present analysis is based on a relatively small number of participants. Accordingly, the interpretation of the statistical procedures used needs to be done in caution due to a difficulty in testing some of the required assumptions underlying some procedures. However, the large effect size found for the difference between groups in the delayed recall trial of the OPAT and in the valid clocks section of the CADT is unlikely to have been greatly influenced by the failure to test these assumptions. In fact, the strength of the findings in light of the small sample described is very encouraging and suggests that these tasks reveal profound differences between these populations. Nevertheless, a further investigation of the results obtained in the present study with a larger sample is desirable.
In the present study, the time that elapsed between the acquisition phase and the delayed recall part of the OPAT was not measured, and therefore it could not be established that there were no group differences in delay time. Although it is unlikely that there was a significant time difference between the groups in this study, a future investigation should ensure this.