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Bader, J., Ismail, A., and Clarkson, J. (1999). "Evidence-based dentistry and the dental research community." (AHRQ's Dental Scholar-in-Residence Program). Journal of Dental Research 78(9), pp. 1480-1483.

The success of dental research in answering clinically relevant questions related to diagnosis, risk assessment, and outcomes of dental care has so far been limited. In some areas, there is evidence that has not been transferred into practice, and for others the evidence is either lacking or of poor quality. Evidence-based dentistry (EBD), if endorsed by the dental profession, may well influence the extent to which society values dental research. This commentary describes the notion of EBD, the current status of clinically relevant evidence in dentistry, and how to build an evidence base. Finally, it discusses the translation of evidence into dental practice. The authors encourage dental researchers to establish an international dialogue and collaboration to strengthen the evidence and improve the processes through which clinicians integrate evidence into their treatment decisions.

Choo, P.W., Rand, C.S., Inui, T.S., Lee, M-L. T., and others (1999). "Validation of patient reports, automated pharmacy records, and pill counts with electronic monitoring of adherence to antihypertensive therapy." (AHRQ grant HS07821). Medical Care 37(9), pp. 846-857.

The quantity of medication used and its timing are two important dimensions of patient adherence to antihypertensive therapy. This study found that patients with hypertension tend to take the prescribed dose of antihypertensive medication more than they tend to take it at the right time intervals. Electronic adherence monitoring revealed that the proportion of prescribed doses consumed was higher (0.92) than the proportion of doses taken on time (0.63). The researchers evaluated the validity of patient report, pharmacy dispensing records, and pill counts as measures of antihypertensive adherence using electronic monitoring as the validation method. The study was conducted among 286 managed care organization members on monotherapy for hypertension. It found that pill counts and refill adherence ascertained from pharmacy dispensing records were more sensitive measures of the number of doses consumed than appropriate dose timing. The relatively low correlation of past pharmacy use with subsequent electronically measured adherence indicated that pharmacy dispensing frequency may have only modest ability to predict future adherence and may misclassify level of medication use.

Mayer, M.L. (1999, December). "Using Medicaid claims to construct dental service market areas." (AHRQ grants HS09330 and HS06993). Health Services Research 34(5), pp. 1047-1062.

Compared with market areas constructed using patient origin data, county-based market areas are an adequate proxy for dental markets. Using the county as the market area also avoids the time and computational costs associated with using a patient origin-based approach and facilitates the use of widely available data, concludes this study. The researchers used Medicaid claims data to construct patient origin-based market areas for dental services and compare constructed market areas with those based on the practice county. Because many providers do not see Medicaid patients, Medicaid patients who seek dental services may actually travel farther than private patients to obtain care. Thus, market areas based on Medicaid patient origin data may overstate the true market for dental services. Smaller geographic areas might better characterize dental market areas for private patients, which further supports the use of single-county markets for dental services.

Wyrich, K.W., Tierney, W.M., and Wolinsky, F.D. (1999). "Further evidence supporting an SEM-based criterion for identifying meaningful intra-individual changes in health-related quality of life." (AHRQ grant HS07763). Journal of Clinical Epidemiology 52(9), pp. 861-873.

Health-related quality of life (HRQoL) instruments, both disease-specific and generic, must be reliable, valid, and sensitive to change. Ideally, an HRQoL instrument also needs established standards for identifying clinically important change for each patient population in which it is used.

Health status measures that are reliable, valid, and sensitive must be able to detect these changes in individuals. This study used the standard error of measurement (SEM) to evaluate intra-individual change on both the Chronic Respiratory Disease Questionnaire (CRQ) and the SF-36 health status questionnaire. After analyzing the reliability and validity of both instruments at baseline among 471 outpatients with chronic obstructive pulmonary disease, the SEM was compared with established minimal clinically important difference (MCID) standards for three CRQ dimensions. A value of one SEM closely approximated the MCID standards for all CRQ dimensions. The authors conclude that the one-SEM criterion should be explored in other HRQoL instruments with established MCIDs.

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Current as of December 1999
AHCPR Publication No. 00-0009

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