Association between health literacy and medication comprehension; attitudes toward reporting adverse events in adults using over-the-counter medicines

Abstract

Background

Self-medication using over-the-counter (OTC) medicines is one of the effective self-care measures in dealing with daily health problems. Health literacy (HL) is critical to ensuring the appropriate use of OTC medicines. The purpose of this study was to evaluate the association between HL and comprehension of medication package inserts among adults who use OTC medicines.

Methods

We conducted a cross-sectional study using a self-administered questionnaire and interviews at 14 drugstores in the Kanto region in Japan from January to February 2020. The study participants were adults aged 20 years or older who purchased OTC medicines. HL was measured using the 14-item HL scale for Japanese adults (Japanese version of HLS-14), and comprehension of medication package inserts was evaluated using an interview survey (label comprehension study [LCS] form). The association between HL and LCS correct response rate and that between HL and attitude toward reporting adverse drug events (ADEs) were assessed using multiple linear regression and logistic regression analyses, respectively.

Results

The analysis included the data of 140 adults, 50 men (35.7%) and 90 women (64.3%), with an average age of 55.2 years. The average HLS-14 score was 51.6, and the overall correct answer rate for reading comprehension was 57.5%. Multiple linear regression analysis revealed that a higher HLS-14 score was associated a higher LCS correct response rate (β = 1.01, p = 0.001). In addition, logistic regression analysis revealed that higher HL was associated with positive attitude towards reporting ADEs to health professionals (adjusted odds ratio = 1.06, p = 0.031).

Conclusions

Adults with higher HL had higher comprehension of OTC package inserts, and higher HL was associated with positive attitude toward reporting ADEs to healthcare professionals. These results indicate that optimal self-medication with OTC medicines requires improving HL among the general public through health education and effective health information provision from pharmacists and registered sales clerks at drug stores.

Keywords:

• Adverse drug events
• Health literacy
• Label comprehension
• Medication package inserts

Supplementary Information

The online version contains supplementary material available at https://doi.org/10.1186/s40545-023-00596-3.

Supplementary Information

The online version contains supplementary material available at https://doi.org/10.1186/s40545-023-00596-3.

Acknowledgements

The authors thank all related persons from the following drugstores for their cooperation during this study: Welcia Yakkyoku stores in Ashikaga Fukui, Adachi Kodo, Kodaira Gakuen-nishimachi, Kumagaya Konan, Yachiyodai Higashi, Ishioka Suginami, Tsukuba Yatabe, Isehara Shiyakusho-mae, Kawaguchi Kitazono, Midori Omama, Ichihara Kokubunjidai, Ota Yabutsuka, and Utsunomiya Tsurutacho and the HAC Drug Shin-yurigaoka store. We are grateful to Prof. Suga Machi from Tokyo Jikeikai Medical University for granting the authors permission to use the HLS-14 questionnaire; Prof. Mochizuki Mayumi from Keio University for granting permission to use the label comprehension study form; Mr. Yamaguchi Keiichi from Daiichi Sankyo Co, Ltd. for granting permission to use sample medical labels; and Ms. Nakajima Ikue from University of Tsukuba for helping with the survey. We also would like to thank Editage (www.editage.com) for English language editing.

Author contributions

SM and TY designed the study. SM and TY conducted the study, supervised by NS and TM. SM analyzed the data. SM drafted the first manuscript, which was critically reviewed by TY, NS, and TM. All authors read and approved the final manuscript.

Funding

This work was supported by an FY 2019 grant from the OTC Self-medication Promotion Foundation, Japan (Grant No. 31-3A-005).

Availability of data and materials

The datasets used and analyzed during the current study are available from the corresponding author on reasonable request.

Declarations

Ethics approval and consent to participate

Ethical approval was obtained from the Ethical Committee of the University of Tsukuba, Faculty of Medicine, Japan (Approval No. 1477). All the participants provided oral consent before participating in this study,

Consent for publication

Not applicable.

Competing interests

The authors declare that they have no competing interests.

Supplementary Information

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