# Trends in psychiatric occupational therapy in Japan: A nationwide analysis using the National Database of Health Insurance Claims and Specific Health Checkups of Japan from 2014 to 2022

## TL;DR

This study analyzed trends in psychiatric occupational therapy in Japan from 2014 to 2022, finding increases in inpatient use and regional disparities.

## Contribution

The study provides a nationwide analysis of psychiatric OT trends in Japan, including gender, age, and regional variations.

## Key findings

- Inpatient psychiatric OT claims significantly increased, especially among the elderly and those under 20.
- Outpatient claims decreased after the start of the COVID-19 pandemic.
- Females had higher inpatient claims than males, but no gender difference was found for outpatients.

## Abstract

Mental health issues are a significant global concern, with psychiatric occupational therapy (OT) playing a crucial role in non‐pharmacological treatment. In Japan, psychiatric OT is reimbursed under the national medical fee system. This study aimed to elucidate changes in psychiatric OT claims in Japan and analyze these changes by gender and age group.

The National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB) Open Data from fiscal years 2014–2022 was used. The number of psychiatric OT claims was analyzed by fiscal year, age group, sex, and region. Simple regression analysis, Mann–Whitney U test, and Spearman's rank correlation were used for statistical analysis.

Inpatient psychiatric OT claims significantly increased from 2014 to 2022, particularly among the elderly (≥70 years) and those aged < 20 years. Outpatient claims significantly decreased after the onset of the COVID‐19 pandemic. Females had significantly higher inpatient claims than males, but no significant difference was observed for outpatients. Substantial regional disparities were found in the implementation of psychiatric OT.

The increase in inpatient psychiatric OT claims, especially among the elderly and younger populations, highlights the growing importance of age‐specific interventions. The decline in outpatient claims raises concerns about the impact of the pandemic on community‐based rehabilitation. Policymakers should consider revising reimbursement schemes to support sustained outpatient OT provision and ensure its integration as a core component of inclusive mental health care systems.