This study aimed to examine the association between home meal preparer and salt intake among haemodialysis patients, including daily dietary status. We hypothesised that salt intake is higher among individuals who rely on meal preparation from others than those who prepare meals by themselves.

Cross-sectional study.

Two medical facilities in Fukushima Prefecture, Japan.

237 haemodialysis outpatients who visited one of the medical facilities between February 2020 and August 2021 and were diagnosed with anuria, defined as urination of

Salt intake amount was calculated from the results of predialysis and postdialysis blood draws, using Watson’s formula based on predialysis weight, predialysis serum sodium level, postdialysis weight and serum sodium level at the end of dialysis.

Salt intake was significantly higher in participants who relied on meal preparation from others (‘relying on others’) than those who prepared meals by themselves (‘self-prepared’) (B=1.359; 95% CI: 0.495 to 2.222). No statistical difference was found between individuals who ate out or ate takeout (‘outsourcing’) and those who prepared their own meals (‘self-prepared’). These results were robust after adjustment for confounding factors.

The present study revealed an association between self-preparation of meals at home and reduced salt intake among dialysis patients. Our findings suggest that whoever is the home meal preparer is possibly a social determinant of salt intake. To improve the prognosis of haemodialysis patients, actively reaching out to the family and assessing their social environment, such as identifying the home meal preparer and, if the patient relies on others for meal preparation, conducting nutritional/dietary guidance for that person, are effective in enhancing salt reduction.

Japanese medical academia continues to depend on quantitative indicators, contrary to the general trend in research evaluation. To understand this situation better and facilitate discussion, this study aimed to examine how Japanese medical researchers perceive quantitative indicators and qualitative factors of research evaluation and their differences by the researchers’ characteristics.

We employed a web-based cross-sectional survey and distributed the self-administered questionnaire to academic society members via the Japanese Association of Medical Sciences.

We received 3139 valid responses representing Japanese medical researchers in any medical research field (basic, clinical and social medicine).

The subjective importance of quantitative indicators and qualitative factors in evaluating researchers (eg, the journal impact factor (IF) or the originality of the research topic) was assessed on a four-point scale, with 1 indicating ‘especially important’ and 4 indicating ‘not important’. The attitude towards various opinions in quantitative and qualitative research evaluation (eg, the possibility of research misconduct or susceptibility to unconscious bias) was also evaluated on a four-point scale, ranging from 1, ‘strongly agree’, to 4, ‘completely disagree’.

Notably, 67.4% of the medical researchers, particularly men, younger and basic medicine researchers, responded that the journal IF was important in researcher evaluation. Most researchers (88.8%) agreed that some important studies do not get properly evaluated in research evaluation using quantitative indicators. The respondents perceived quantitative indicators as possibly leading to misconduct, especially in basic medicine (strongly agree—basic, 22.7%; clinical, 11.7%; and social, 16.1%). According to the research fields, researchers consider different qualitative factors, such as the originality of the research topic (especially important—basic, 46.2%; social, 39.1%; and clinical, 32.0%) and the contribution to solving clinical and social problems (especially important—basic, 30.4%; clinical, 41.0%; and social, 52.0%), as important. Older researchers tended to believe that qualitative research evaluation was unaffected by unconscious bias.

Despite recommendations from the Declaration on Research Assessment and the Leiden Manifesto to de-emphasise quantitative indicators, this study found that Japanese medical researchers have actually tended to prioritise the journal IF and other quantitative indicators based on English-language publications in their research evaluation. Therefore, constantly reviewing the research evaluation methods while respecting the viewpoints of researchers from different research fields, generations and genders is crucial.