Dentists' Understanding of Diagnostic Test Results and Treatment Efficacy.

Study Overview
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Brief Summary
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There is little evidence on how best to present diagnostic and treatment effect information to dentists and whether this makes any difference to their understanding of the information given and clinical management. The objective of this study is to assess the influence of different formats for presenting diagnostic test results and treatment efficacy on dentists' understanding and on their reported clinical management. The hypothesis is that presenting diagnostic test and treatment effectiveness results using natural frequencies influences the threshold for treatment and improves interpretation of tests results compared to conditional probabilities and percentage differences. A group of dentists recruited from postgraduate courses were randomized to two of four arms, being two arms of a hypothetical realistic diagnostic scenario (a) and two arms of a hypothetical realistic treatment scenario (b): a1) diagnostic test results presented in conditional probabilities; a2) diagnostic test results presented in natural frequencies; b1) treatment efficacy presented in percentages; b2) treatment efficacy presented in natural frequencies. The main outcome measures were the correct answer as to whether disease was actually present (post-test probability) and the correct answer as the number of patients that would benefit from the treatment (efficacy). Secondary outcome measures included the decision whether to treat or not treat the hypothetical patient.

Official Title
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The Influence of Different Formats for Presenting Diagnostic Test Results and Treatment Efficacy on Dentists' Understanding and on Their Reported Clinical Management.

Conditions
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Health Education

Intervention / Treatment
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* Other: Dental health information form


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Graduated dentist undergoing a postgraduate course in a public university in Rio de Janeiro. Exclusion Criteria: None.
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Diagnostic percentages.<br>Dentist receives diagnostic test results presented in conditional probabilities. | Other: Dental health information form<br>* The format in which dentists receive information about diagnostic test results and efficacy of treatment.<br>|
| Experimental: Diagnostic frequencies<br>Dentist receives diagnostic test results presented in natural frequencies. | Other: Dental health information form<br>* The format in which dentists receive information about diagnostic test results and efficacy of treatment.<br>|
| Active Comparator: Treatment percentages.<br>Dentist receives treatment efficacy presented in percentages. | Other: Dental health information form<br>* The format in which dentists receive information about diagnostic test results and efficacy of treatment.<br>|
| Experimental: Treatment frequencies.<br>Dentist receives treatment efficacy presented in natural frequencies. | Other: Dental health information form<br>* The format in which dentists receive information about diagnostic test results and efficacy of treatment.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The probability that a patient will have a dental cavity as assessed by a dentist. | The assessement by the dentist was based on a questionnarie containing a clinical hypothetical situation and the result of a bite-wing radiographic exam. | Up to 20 minutes | 
| The number of patients that will benefit from systemic antibiotics adjunct to periodontal treatment as assessed by a dentist. | The assessement by the dentist was based on a questionnarie containing a clinical hypothetical situation and the information about the usual efficacy of systemic antibiotics adjunct to periodontal treatment. | Up to 20 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The number of dentists that would recommend the use of systemic antibiotics adjunct to periodontal treatment in the clinical management of a patient with periodontal disease. | The recommendation by the dentist was based on a questionnarie containing a clinical hypothetical situation and the information about the usual efficacy of systemic antibiotics adjunct to periodontal treatment. | Up to 20 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Communication Barriers, Persuasive Communication, Risk