Most problem-based learning models also contain student reflection components as a means of self-evaluation" (Knowlton & Sharp, 2003, pp. 5-6). Although the positive effects of using a problem-based learning approach have been documented in a number of studies, the findings of other studies have indicated that problem-based learning may not compare favorably with more traditional teaching methods with regards to student's knowledge base, technical skills, or the resources expended; however, Dadd (2009) suggests that the benefits of using a problem-based learning approach justify the additional resources this method requires. Moreover, Simons et al. (2004) report that students using a problem-based learning approach "tend to develop more positive attitudes toward learning than students in more traditional environments" (p. 214).

There are also some other challenges to applying the problem-based learning approach in healthcare settings that must be taken into account when considering the adoption of this method and how it will be implemented and administered. In this regard, Dadd notes that these challenges include "development of further problems and the interaction of professionals in this development, the attitude of faculty to the teaching method" (2009, p. 2). Notwithstanding these foregoing challenges, many authorities agree that the problem-solving learning approach provides an excellent return on the investment of the resources expended (Lam, 2004; Alavi, 1999). Indeed, Simons et al. (2004) emphasize that the findings from a meta-analysis of problem-based learning models used in medical schools showed that although students who used traditional educational methods typically scored higher on standardized measures of basic science knowledge than those in problem-based programs, the students who used the problem-based learning approach appear to have acquired better long-term recall of the subject matter because of the deeper understanding they gained of the subject matter presented. This outcome is congruent with the observation by Albion (2003) that, "Because problem-based learning involves the learner in working with, rather than simply observing, a case, it ought to intensify the effect of a case on development of self-efficacy. Thus problem-based learning appears to offer particular benefits for developing both expertise and the capacity to apply it" (p. 243).

In tertiary healthcare settings, the objective structured clinical examination may be the most appropriate for evaluation purposes using a problem-based approach for advanced learners such as residents. According to Sweet, Huttly and Taylor (2003), "The objective structured clinical examination (OSCE) using simulated patients with video feedback is becoming widely used in the summative assessment of competence" (p. 47). Evaluation using the OSCE approach involves having students complete various tasks within a specified amount of time in a controlled environment which is frequently simulated (Sweet et al., 2003). Although they will vary in number, the OSCE approach uses numerous stations (typically between 20 and 40) to assess student performance on various realistic tasks (Sweet et al., 2003). Each station uses a real or simulated patient and the student's performance at each station is evaluated by the examiner using a checklist to provide objective assessment (Sweet et al., 2003). In addition, Wessel, Williams, Finch and Gemus (2003) report that, "Written stations may be included to evaluate the students' interpretation and application of findings or their ability to plan further assessment or treatment" (p. 266).

Yet another challenge in using this problem-based learning approach is how to maximize its effectiveness and student retention of the knowledge they have acquired. For this purpose, following the completion of the OSCE, Sweet and her associates emphasize the need for feedback to students in order to realize the greatest return on the investment of time and resources. In this regard, these authorities emphasize that, "To simply tell learners that they have either passed or failed and can or cannot progress to the next summative hurdle is of little value for their experiential learning. Feedback on knowledge, competence, performance and outcome should be given as soon after the assessment as is practicably possible" (p. 47). The evaluation criteria used by examiners should be made available to students and explanatory comments should be used to justify negative as well as positive evaluations (Sweet et al., 2003).

A final challenge involved in a problem-based learning approach in a tertiary healthcare setting relates to the manner in which teaching personnel are selected. According to Alavi (1999), in order to ensure the success of these initiatives, staff members who are selected for teaching problem-based curricular offerings must be provided with the information they need to make an informed decision concerning their abilities and desire for teaching these types of courses (Alavi, 1999). In this regard, Alavi notes, "Consistent with a problem-based learning approach, it is important that applicants be given opportunity to assimilate this information by having time to talk informally with the teaching team, and with students, and by attending problem-based tutorials...

125).
When staff members accept such teaching assignments, it is also important to provide them with enough time to complete relevant orientation courses, identify potential problem areas and receive answers to questions as they arise (Alavi, 1999). According to Alavi, though, the time and resources spent in helping new healthcare educators become more familiar and comfortable with the roles is justified by the return on these investments. Although these issues are important for all staff members, they are even more important for clinical and part-time staff. In this regard, Alavi emphasizes that, "Not only will these people have less direct access to peer support and evaluation, the integrity of the problem-based curriculum will be maintained only to the extent to which such staff feel integral to the course" (1999, p. 125). Notwithstanding these challenges, though, it is clear that the problem-based learning approach can provide a number of valuable outcomes when these programs are implemented and administered in a thoughtful fashion.

Conclusion

Problem-based learning approaches were shown to be an increasingly popular method of teaching complex subject content in tertiary healthcare settings. Although the research showed that there remains a lack of standardized techniques for using the problem-based learning approach, there are some solid guidelines available to help healthcare educators formulate effective curricular offerings that can help learners become more proficient by solving realistic problems in context. The research also showed, though, that some authorities believe that the problem-solving learning approach is less effective than traditional teaching methods while others suggest the outcomes achieved are comparable. Other authorities, however, emphasize that by helping learners retain the content longer and synthesize this knowledge with conventional learning, the use of the problem-based learning approach provides a more significant return on the investment of resources that are required for its use. The adoption, implementation and administration of problem-based learning approaches was also shown to be marked by several challenges, including what type of content should be included, developing new problems for use in curricular offerings as well as the attitude of other staff members concerning this teaching approach. Another challenge identified in the literature review related to the need to ensure that staff members selected to deliver problem-based learning were provided with a sufficient amount of time to make an informed decision concerning whether they wanted to participate in these programs of instruction and to gain the requisite expertise in their use. In the final analysis, the use of the problem-based learning approach was shown to provide a wide range of valuable outcomes if the process is implemented and administered in a thoughtful fashion that takes these constraints into account.