Aim: To evaluate the accuracy of commonly advocated caries risk assessment (CRA) tools in preschool children and to search for evidence whether or not this process provides better oral care and less caries in the future. Methods: As an update of a previous systematic review, a search of electronic databases for relevant literature published between 2008 and 2018 was performed with aid of predetermined search strings. We considered only true prospective trials validating baseline risk categories over at least a 12-month period, and extracted the predictive values and assessed the quality of the papers by the QUIPS tool for prospective studies. Results: Six studies were included, reporting on three manual checklists and two software tools. The National University of Singapore model displayed a good accuracy in two studies, while the accuracy of Cariogram ranged from poor to good in various populations. The manual checklists were only validated in one study each and displayed limited to poor accuracy. No study was identified that addressed questions around the long-term benefits of CRA. Conclusions: This systematic review showed a relative paucity of prospective trials validating the existing caries risk assessment tools in preschool children and the question whether or not the CRA process results in better oral care remained unanswered. Although the accuracy was far from excellent, we still recommend the CRA tools in paediatric dentistry practice because the desirable effects most likely outweigh the undesirable effects.