Factors influencing decision‐making ability of the patient receiving home medical care

Abstract Background Patients' decision‐making ability is a substantial barrier to end‐of‐life conversations with doctors. This study aimed to examine factors influencing this ability. Methods Altogether, 914 doctors from Japanese home care supporting clinics providing home medical care as of February 2019 participated in this study. Data were collected through an anonymous mailed survey between April and May 2019. Results Stepwise multiple linear regression analysis of factors influencing patients’ decision‐making ability revealed the following significant factors: (a) independence level in the daily life of older adults with dementia (B: −0.52), (b) disease name (B: 0.20), and (c) family structure (B: 0.12). Conclusions Patients' decision‐making ability regarding conducting end‐of‐life conversations with doctors was characterized; thus, (a) they did not have cognitive impairment, (b) they had cancer, and (c) they lived with a spouse.


| INTRODUC TI ON
Japanese guidelines for end-of-life health care and decision processes indicate the importance of providing end-of-life care based on the patient's decision-making ability 1 . Silveira et al 2 revealed that many patients lacked the ability to make decisions when they needed to and one-fourth of older patients needed a surrogate for end-of-life decision making. This ability is a substantial barrier to end-of-life conversations with doctors [3][4][5] ; however, predicting who will require surrogate decision making may be difficult 2 . Therefore, this study aimed to examine factors influencing this ability.

| Sample
An anonymous survey was mailed to 914 doctors of home care supporting clinics (HCSCs) that were certified by the Japanese Ministry of Health, Labour and Welfare. These doctors were full members of the Japan Network of Home Care Supporting Clinics as of February 2019. This study was performed between April and May 2019; with a cover letter clearly stating the purpose of this study, the right to refuse to participate, strict safeguarding of the data except for the publication of anonymous statistically analyzed data, which does not TA B L E 1 The relationships between decision-making ability and the characteristics of both respondent doctors and patients Note: Simple linear regression analysis, dependent variables: The patient had sufficient decision-making ability from 1 (highly disagree) to 5 (highly agree); b: standardized partial regression coefficient; a multiple answers allowed; N = 196. b https://www.mhlw.go.jp/file/06-Seisa kujou hou-12300 000-Rouke nkyok u/00000 77382.pdf; cited May 17, 2020. (in Japanese); a is the explanation of Disease incidence. specify individuals. Informed consent was not required in this study.
It was assumed that each subject agreed to join the study of his/ her own free will by returning the answered questionnaire. Patients under 10 years old were excluded.

| Measurements
We asked respondents to provide information about one recent patient with whom they conducted end-of-life conversations. To assess the patient's decision-making ability, we asked the doctors to assign a score ranging from 1 (highly disagree) to 5 (highly agree) for: "Did the patient have sufficient decision-making ability?"

| Statistical analysis
To analyze the factors influencing this ability, we conducted simple linear regression analysis followed by stepwise multiple linear regression analysis using SPSS 22.0J software for Windows.    Stepwise multiple linear regression analysis, dependent variables: the patient had sufficient decision-making ability from 1 (highly disagree) to 5 (highly agree); independent variables: variables whose p-value was less than 0.001 in the simple linear regression analysis; b: standardized partial regression coefficient; R 2: determination coefficient; N = 196.

| D ISCUSS I ON
TA B L E 2 Factors influencing decisionmaking ability of the patient receiving home medical care rate was only 23.4%. Second, as we asked the HCSCs to volunteer information about recent patient(s), the result was too few patients for analysis. Third, there were many diseases and conditions with very low incidence, and the numbers were too small to analyze, so the named diseases were limited to only five which involved 10 or more patients (>5% incidence) reported in this study. Fourth, although end of life has a wide meaning as a concept and there are multiple definitions, we did not limit the inclusion (into this study) by a fixed definition of end-of-life conversation in this questionnaire.
In future studies, we should examine a greater number of patients in this situation.

| CON CLUS ION
The characteristics of patients with sufficient decision-making ability, as assessed by doctors, were as follows: (a) having no cognitive impairment, (b) having cancer, and (c) living with a spouse. For patients who may withhold end-of-life preferences, more specific and well-organized support is necessary.

ACK N OWLED G EM ENTS
We wish to thank the doctors that participated in this study. This work was supported by JSPS KAKENHI (17K12199), Grant-in-Aid for Scientific Research (C).

CO N FLI C T O F I NTE R E S T
The authors have stated explicitly that there are no conflicts of interest in connection with this article. This survey protocol was approved by the ethics committee at Kio University, Nara, Japan (approval number: H30-21).