Analysis of agreement between Visual Analogue Scales (VAS) and numerical questions to assess perception of teratogenic risks in treatment with drugs and radiotherapy in women

Abstract

Objectives: to evaluate the agreement between Visual Analogue Scales (VAS) and numerical questions as a way of assessing the perception of teratogenic risk of treatment with drugs and radiotherapy. Methods: the sample comprised 144 pregnant and 143 non-pregnant women consecutively recruited at public health centers in Porto Alegre, in the State of Rio Grande do Sul, from February to August 2011. The perception of risk for congenital malformations in the general population and the perceptions of teratogenic risk for exposure to acetaminophen, meto-clopramide, misoprostol and radiotherapy were measured using VAS and numerical questions. The agreement between the results of the two techniques was tested using a Bland-Altman plot. Results: the medians for the perceptions measured using VAS were higher than those obtained using numerical questions for all variables. The perception of risk for acetaminophen showed the lower bias of the two techniques (bias=13.17; p<0.001) and exposure to radiotherapy, the higher (bias=25.02; p<0.001). Conclusion: there was no agreement between the measurements obtained using the two techniques for any of the risk perceptions under study. Risk perceptions were higher using VAS, for all kinds of exposure. Studies should be conducted to assess whether there is overestimation in other situations and social contexts owing to the use of VAS.

Risk management of teratogenic medicines: A systematic review

“…In their research, they concluded that there was no agreement between the two methods in estimating teratogenic risk. (Pons et al, 2014). Furthermore, it is recommended that future research exploring perceptions of teratogenic risk needs to utilize qualitative methods in addition to quantitative research.…”

“…There is an ongoing debate on the utility of visual analogue scales in measuring risk perception. Some argue that responses of participants to questions including a visual analogue scale tend to cluster around the middle point of the scale and might over‐estimate the risk when it is low (Pons, Guimarães, Knauth, & Pizzol, 2014; Sanz et al, 2001), while others suggest that a visual analogue scale can provide a wide range of responses that can be chosen by research participants (Harland, Dawkin, & Martin, 2015). Pons et al investigated the level of agreement between a visual analogue scale and a numeric scale in estimating the teratogenic risk.…”