Conducting a Traditional or Comprehensive Search and the Use of Filters

Without knowing about or using the MeSH or Advanced search features, the most common way of beginning a search is to type in the main search term, tooth erosion, on the Homepage (Figure 8).

Figure 8. Beginning a Traditional/Comprehensive Search.

Next click on Search to see the results, of which 3041 citations were found (Figure 9a). In order to narrow these results to the most current and highest levels of evidence, use the filters that appear on the left-hand column. Scanning down the column you have choices related to Article types, Text availability, Publication dates, Species, and Show additional filters. Some of the additional filters include Languages, Sex, and Ages.

Figure 9a. Results of a Traditional/Comprehensive Search.

Of all the filters, perhaps the most important is Article Types since it allows you to search for studies by levels of evidence. Although Clinical Trial and Review appear as the default setting, by clicking on Customize... a menu of options appear (Figures 9b and 9c). As you scroll down, you will see Meta-Analysis, Practice Guideline, Randomized Controlled Trial and Systematic Review. By checking these off and clicking on the Show button, these are placed now on the main page (Figure 9d).

Figure 9b. Customizing Article Types.

Figure 9c. Customizing Article Types (Continued).

Figure 9d. Result of Adding Options under Article Types.

Image of Result of Adding Options under Article Types.

Beginning with clicking on Practice Guideline, the highest level of evidence, the 3041 citations are narrowed to 5 (Figure 10), which is much more reasonable to review. However, notice that the most recent one was published in 2008.

Figure 10. Using Filters to Narrow Citations to the Highest Level of Evidence, Practice Guideline.

If no Practice Guidelines were identified or none of those found answer your question, then re-run the search. First clear the filter by clicking on “Clear all” to remove its selection. Next, click on Meta-Analysis, the next highest level of evidence. In this case, 11 citations are identified (Figure 11).

Figure 11. Using Filters to Narrow Citations to the Highest Level of Evidence, Meta-Analysis.

If no Meta-Analysis is found, then re-run the search again by clicking on “Clear all” to remove Meta-Analysis and click on Systematic Reviews, the next highest level. Continue this process so that you are able to identify the highest levels of evidence. For a review of levels of evidence and the hierarchy that exists to guide clinical decision making see Evidence-Based Decision Making: Introduction and Formulating Good Clinical Questions.1

If there had been a large number of citations, another option is to use the “Publication dates” filter to limit the findings to the past 5 or 10 years. Also, if focusing on a specific age group or sex, click on Show additional features and select the appropriate group (Figure 12).

Figure 12. Additional Filters to Narrow Citations.