Settings and Participants
The provincial field survey was carried out in Jiangsu, a developed province located on China's east coast with 13 prefecture-level cities and 85 million people in 2022. A 3-stage stratified sampling was applied to select participants. First-stage, all prefecture-level cities in Jiangsu were stratified into three groups on the economic-geographic characteristics in 2022, then we selected one prefecture-level city from each group. Thus, Lianyungang (GDP 401 billion CNY), Yangzhou (GDP 711 billion CNY), and Changzhou (GDP 950 billion CNY) were selected, which are respectively located in northern, central, and southern Jiangsu. Second-stage, we chose one district in each sampling prefecture-level city on the basis of annual GDP per capita, thus, districts Ganyu in Lianyungang, Guangling in Yangzhou, and Wujin in Changzhou were chosen. Last-stage, three hospitals (one each for primary, secondary, and tertiary separately) from each sampling district were selected as the specific study sites. This survey was initially designed to enroll 700 adult outpatients in each sampling prefecture-level city at a ratio of 3:4:7 (primary : secondary : tertiary), for 2,100 participants in total.
The national online survey was implemented via WJX (an online questionnaire survey platform owned by Changsha Ranxing Information Technology Co., LTD in China). WJX recruited participants who were willing to engage in the survey from its sample bank of 6.2 million real-ID registered members. The survey was self-administered and accessible at any time during the designated period. The participants were allowed to complete the survey only once and could leave at any time. Upon completion of each survey, WJX awarded the contributing participants with 7 cash rewards. This survey was initially designed to enroll a total of 1600 adult participants with outpatient records in the past 3 months.
According to the sample size calculation formula as follows with an assumption of 20% prevalence of IMSU, the sample size in the provincial field and national online surveys were both considered sufficient .
Data Collection
The field data were collected in July 2023 by using a face-to-face interview at the sampling hospitals. The interviews were conducted among the outpatients using a structured questionnaire by trained undergraduate and master students from Nanjing Medical University School of Health Policy & Management. To ensure quality, completed questionnaires were carefully double-checked via the mutual check of team members and the sampling inspection of quality supervisors at the end of each day.
The online data were collected in March 2024 by WJX under our supervision. For making the samples more nationally representative, we required provincial distribution characteristics of the samples that WJX collected were similar to the data published by the National Bureau of Statistics of China in 2022. In addition, we asked WJX to execute 3 waves of real-time quality control survey , each round spaced one week with around 500 samples.
Variables and Measures
Internet Medical Services Utilization
The variables on status, patterns, and preferences were constructed to describe IMSU. Given that all participants in the national online survey claimed they have accessed IMSU in the previous 12 months. Therefore, we used the times of patients accessed IMSU in the previous 12 months to describe the status of IMSU, which was categorized into two groups (“unused”: 0 times; or “used”: >= 1 times) in the provincial field survey, and two groups (“low frequency”: less than first quartile, <= 3 times; or “high frequency”: more than third quartile, >= 6 times) in the national online survey.
The following three dimensions were represented by the times of patients visited common platforms, primary reasons, and main purposes for IMSU in the previous 12 months to describe the patterns of IMSU. The common platforms were divided into “Internet hospital” (physical hospital operating online), “private platform” (private for-profit medical services platforms, e.g., Ali Health), and “search engine” (web applications that return links to relevant web pages through keywords or phrases entered, e.g., Google). The primary reasons covered the diseases of “acute” (e.g. sinus infection), “allergic” (e.g., urticaria), “chronic” (e.g., hypertension), “mental” (e.g., anxiety), “minor” (e.g. fever), and “urogenital” (e.g., prostatitis). The main purposes included “health monitor”, “purchase drugs”, “routine visit”, “subsequent visit”, “teleconsultation”, “telediagnosis”, and “telesurgery”. The “tele” series medical services (e.g., telediagnosis) were defined as subordinate hospital initiates requests to superior hospital via digital technology for inability to meet the patients' needs in China, which are more deeper IMSU.
The IMS preferences (IMSP) were measured with a 4-dimension (common platforms, main purposes, media forms, and relative prices) 7-point (from 1= Strongly Disagree to 7 =Strongly Agree) Likert scale (see Additional file 1) developed by our research group. The dimension of common platforms included 3 items that focused on “Internet hospital”, “private platform”, and “search engine”. The dimension of main purposes included 3 items that focused on “routine visit”, “purchase drugs”, and “telesurgery”. The dimension of media forms included 3 items that focused on “image & text”, “phone call”, and “FaceTime”. The dimension of relative prices included 3 items that focused on “less than offline”, “similar to offline”, and “higher than offline”. The scale passed the validity and reliability test, the KMO value was 0.87, p<0.001 for the Bartlett test, and the Cronbach's α value for the dimension of main purposes was the lowest 0.69 (see Additional file 2).
Demographic Factors
Demographic characteristics used in this study included age (a continuous variable, categorized into “<60 years old”; or “>=60 years old”), gender (“female”; or “male”), habitat (“rural”; or “urban”), surveyed cities (“Lianyungang”; “Yangzhou”; “Changzhou”, in the provincial field survey), surveyed areas (“eastern”; “central”; “western”; or “northeast”, in the national online survey).
Socio-economic Factors
The variables reflecting socio-economic factors were medical insurance (“without”; or “have”), work institutions (“non-office”: non-government/enterprise; or “office”: government/enterprise), net access (“occasionally”; “frequently”; or “everyday”), education level (“basic”; “secondary”; or “higher”), surveyed hospital level (“primary”; “secondary”; or “tertiary”), and annual disposable income (“<=30,000 CNY”; “30,000 - 150,000 CNY”; or “>=150,000 CNY”).
Health Status
Health status included self-rated health (categorized into 4 groups: “very-unhealth”; “unhealth”; “sub-health”; or “health”), and the number of chronic diseases (a continuous variable) which comprised cardiovascular (e.g., hypertension), cerebral (e.g., epilepsy), digestive (e.g., pancreatitis), immune (e.g., lupus), motor (e.g., osteoporosis), respiratory (e.g., asthma), tumorous (e.g., cancer), and urogenital (e.g., prostatitis).
Statistical Analysis
Chi-square test was employed to compare structural differences in demographic, socio-economic, and health status characteristics between the respondents from provincial field and national online surveys. For IMSP scale, Cronbach's α coefficient was adopted to test the reliability, KMO value and Bartlett test were used to assess the validity. Binary logistic regression model (BLRM) with an enter method was employed to evaluate the association between potential predictors (demographic factors, socio-economic factors, and health status) and IMSU status. The score of IMSP was included to adjust BLRM, and the goodness of fit for BLRM was assessed based on the Hosmer-Lemeshow test. StataSE version 15.0 (StataCorp, College Station, TX, U.S.) was used for data cleaning, and SPSS version 25.0 (IBM Corp, Armonk, NY, U.S.) was used for BLRM.
Ethics approval and consent to participate
The Ethical Committee approved this study in the Nanjing Medical University Institutional Review Board Consent Letter No. (2023)139. All methods were carried out in accordance with relevant guidelines and regulations. Patients were informed of the study's purpose and procedures. In additional, written informed consent to participate in this study was provided by the subjects.