Study Details
Study Design
This longitudinal database, HKADA, records middle-aged and older Hong Kong Chinese adults’s multidirectional developmental trajectories, including their physical, cognitive, and psychosocial development. The current research project made use of a mixture of data collection modes, including self-reported questionnaires, one-on-one in-depth interview, and standardized physical and cognitive assessments, to provide empirical baseline data for HKADA. Upon funding availability, biennial follow-up assessment for the same participant will be carried out using the identical data collection methods (i.e., self-reported questionnaires, one-on-one in-depth interview, and standardized assessments).
Sampling and Participants
Multiple efforts were made to obtain a representative sample for HKADA. The sample was selected by first stratifying the computerized addresses records of Census and Statistics Department by the geographical area and the type of quarter, then applied the systematic replicate sampling. A total of 12 replicates conveying 7076 quarters/addresses were obtained from the Census and Statistics Department as the sampling frame. All residential addresses in the 18 district councils were evenly distributed in those 12 strata, with approximately 500 addresses each. Invitation to join the research study was sent to these 7076 residential addresses by mail. However, due to the fourth wave of the COVID-19 outbreak during the beginning stage of this project (November 2020 to May 2021), the response rate (1.27%) was unsatisfactorily low. Accordingly, alternate sampling methods were adopted to reach out target participants in the community during the COVID-19 pandemic. In particular, invitations were sent to all district councilors in Hong Kong, non-governmental organizations serving middle-aged and older people, and labor unions and professional associations by letters or emails, followed up by phone calls. Ninety-four non-governmental organizations and 590 labor unions were contacted. Among them, eighteen non-governmental organizations (response rate: 19%) and 20 labor unions (response rate 3%) agreed to promote this project among their members through emails, calls, or flyers.
A total of 2392 participants were successfully recruited and took part in the interview and assessments. Adopting the age criterion of CHARLS and HRS (Zhao et al., 2012), all participants in the current project were 45 years or older and residing in households (non-institutionalized individuals). Other inclusion criteria were (1) being Chinese, (2) spoke either Cantonese or Mandarin, and (3) had been living in Hong Kong for at least three months in the past six months (referenced to the Census and Statistics Department’s definition of a usual resident). One participant was excluded from the final sample as he/she refused to report his/her personal information after multiple attempts. Therefore, the final sample for the following analyses is 2391. Among them, there were 227 pairs of couples where both partners (n = 454; 18.99% of the sample) participated in this project.
There were 193 participants who only partially completed the data collection procedure (e.g., those who only completed the self-reported questionnaire but not the face-to-face assessment; please see Section Data Collection Procedures for a detailed description of the mode of data collection). The major reasons of these partially completed cases included the concerns of being infected with the COVID-19 virus and invalid contact means. The incomplete cases were comparatively younger than the participants who completed all assessments (Mdiff = —4.43, p < .001). However, in terms of their gender and education level, there were no significant differences between the incomplete and completed cases.
Data Collection Procedures
Ethical approval was first sought from the Human Subjects Ethics Sub-committee of the affiliated university (number: 3-3-202002-02) before the commencement of data collection. In the initial stage of the project using the sampling frames obtained from the Census and Statistics Department, an invitation letter for participation was sent to the randomly drawn addresses, in which the objectives and nature of the study was stated. Eligible individuals could reply to the letter to indicate their willingness to participate in the study. This sampling method was later complemented by the alternate sampling strategies reported in Section Sampling and Participants.
Given the large volume of information gathered throughout the data collection period, both self-reported questionnaire and one-on-one structured interview and assessment were adopted. A consent form was first obtained from each participant before collecting their personal information. The self-reported questionnaire covered demographic variables, health, work, retirement preparation and psychological characteristics, which took approximately 30 minutes to finish. Depending on the preference of the participants, participants could fill in either the printed or electronic version of the self-reported questionnaire that was sent to the participants by post or by email, respectively. Assistance was provided to the participants who could not complete the self-reported questionnaire themselves due to their education level or eyesight problems. Upon receiving the returned self-reported questionnaire from participants, a one-on-one interview, together with the standardized physical and cognitive assessments, was arranged and conducted by trained interviewers.
The research team of HKADA contacted participants by phone or instant message to notify them in advance of the face-to-face interview and physical and cognitive assessments. The interview and assessments took place in the Psychology Laboratories of the affiliated university or the residence of the participants, with exceptions for a small part of participants where the interview took place in the community centers where they were recruited. Each interview and assessments were carried out by a trained interviewer, and the eligible respondents answered all questions in the main interview about themselves. Due to the social distancing policies imposed during the COVID-19 outbreak (the fifth wave during January to May 2022), a small proportion of participants (< 5%) completed the interview using telephone. Similar practice (i.e., telephone interviews) has also been used in other panel studies during the COVID-19 pandemic (e.g., HRS: Beydoun et al., 2022). It took about 60 — 90 minutes to complete the interview and assessments. Each participant was given HKD150 as a token of appreciation for his/her participation in the entire interview and assessments. On average, the entire questionnaires and assessments were completed in 1.5 — 2 hours.
Modules Included in the Baseline Study
The survey was written in Chinese, with the use of the validated Chinese version for most of the measurement scales. Survey instrument is structured in modules as shown below:
1) Demographic Information
1.1) Personal Information
1.2) Spouse Information
1.3) Parent Information
1.4) Children Information
1.5) Household and Expenses
1.6) Social Security
2) Socioeconomic Status
2.1) Subjective Socioeconomic Status
2.2) Assets and Property
3) Physical Health
3.1) General Health
3.2) Chronic Disease(s)
3.3) Physical Functioning
3.4) Physical Auxiliary and Disability
3.5) Objective Measurement for Physical Health
4) Behavioral Risks
4.1) Smoking, Alcohol Use, and Delay Medial Treatment
4.2) Health Behaviors
5) Cognitive Function
6) Psychological Characteristics and Well-being
6.1) Sense of Control
6.2) Resilience
6.3) Personality
6.4) Future Time Perspective
6.5) Psychological Well-being
6.6) Mental Health and Depressive Symptoms
7) Healthcare Utilization
8) Employment and Retirement Preparation
8.1) Employment
8.2) Retirement Planning
8.3) Retirement
8.4) Pension, Insurance, and Annuity
9) The Use of Information and Communication Technology and Intention of Knowledge Update / Skill Update
9.1) The Use of Information and Communication Technology
9.2) Online and Board Game
9.3) Intention of Knowledge Update / Skill Update
10) Social Support
10.1) Support
10.2) Community Support
11) Living Arrangement
12) Expectations toward Future
13) Participation in Volunteering Activities
Reference
Beydoun, H. A., Beydoun, M. A., Weiss, J., Gautam, R. S., Hossain, S., Alemu, B. T., & Zonderman, A. B. (2022). Predictors of Covid-19 level of concern among older adults from the health and retirement study. Scientific Reports, 12, 4396.
Zhao, Y., Hu, Y., Smith, J. P., Strauss, J., & Yang, G. (2012). Cohort profile: the China health and retirement longitudinal study (CHARLS). International Journal of Epidemiology, 43(1), 61-68.