Development of a Short Questionnaire for the Screening for Vitamin D Deficiency in Italian Adults: The EVIDENCe-Q Project.

Background

To develop and validate a questionnaire for the screening of Vitamin D in Italian adults (Evaluation Vitamin D dEficieNCy Questionnaire, EVIDENCe-Q).

Methods

150 participants, attending the 11Clinical Nutrition and Dietetics Operative Unit, Internal Medicine and Endocrinology, Istituti Clinici Scientifici Maugeri IRCCS, of Pavia were enrolled. Demographic variables and serum levels of vitamin D were recorded. The EVIDENCe-Q included information regarding factors affecting the production, intake, absorption and metabolism of Vitamin D. The EVIDENCe-Q score ranged from 0 (the best status) to 36 (the worst status).

Results

Participants showed an inadequate status of Vitamin D, according to the current Italian reference values. A significant difference (p < 0.0001) in the EVIDENCe-Q score was found among the three classes of vitamin D status (severe deficiency, deficiency and adequate), being the mean score higher in severe deficiency and lower in the adequate one. A threshold value for EVIDENCe-Q score of 23 for severe deficiency, a threshold value of 21 for deficiency and a threshold value of 20 for insufficiency were identified. According to these thresholds, the prevalence of severe deficiency, deficiency and insufficiency was 22%, 35.3% and 43.3% of the study population, respectively. Finally, participants with EVIDENCe-Q scores <20 had adequate levels of vitamin D.

Conclusions

EVIDENCe-Q can be a useful and easy screening tool for clinicians in their daily practice at a reasonable cost, to identify subjects potentially at risk of vitamin D deficiency and to avoid unwarranted supplementation and/or costly blood testing.