Abstract

Purpose: Radiation safety is one of the main concerns for thyroid cancer patients and their caregivers in radioiodine therapy. Even though there is a plethora of research describing radiation exposure to family members of patients, no meta-analysis study has been carried out on this subject. In this study, the doses received by the family members of the patients treated with 131I were investigated. Methods: A systematic literature search was carried out using databases of Web of Science, PubMed, Embase, Scopus, and Google Scholar without the beginning date restriction until December 2022. The meta-analysis was performed using the random-effects model, and the doses received by caregivers were calculated as the effect sizes. Results: This meta-analysis retrieved a total number of 2080 family members of thyroid cancer patients. The pooled estimates for radiation exposure to family members of inpatients and outpatients treated with 131I were calculated as 0.4 mSv (95 CI 0.26–0.55 mSv) and 0.54 mSv (95 CI 0.48–0.60 mSv), respectively. The shapes of Begg’s funnel plots seemed asymmetrical for both groups of studies evaluating the doses received by the family members of inpatients and outpatients (Begg’s test p = 0.011 and < 0.001, respectively) which demonstrate the existence of publication bias in the results of included studies. The level of significance calculated in meta-regression analysis to evaluate the effects of administered activity, male sex ratio, and study quality score on the doses received by the family members of the inpatients treated with 131I were p = 0.526, 0.759, and 0.129 respectively. The p-values obtained to evaluate the effects of administered activity, age average of the caregivers, male sex ratio, and study quality score on the doses received by the family members of the outpatients treated with 131I were p = 0.496, 0.974, 0.010, and 0.636 respectively. The study location significantly modifies doses received by family members of patients (both p < 0.001). Conclusion: There are considerable radiation protection considerations for the family members of patients after radioiodine administration. The results of this study showed that caregivers received doses of less than 1 mSv. There are no radiation hazards for family members of patients treated with 131I and the conventional advice provided by the radiation protection advisor is enough. The socioeconomic factors, lifestyle, and literacy levels of the patients’ family members determined the compliance of the caregivers with safety recommendations and therefore modifies the doses received by family members. © 2023, The Author(s), under exclusive licence to Italian Association of Nuclear Medicine and Molecular Imaging.