An integrated mixed methods approach will be used. We will measure the economic effects of care dependence by nesting the study within the pre-existing baseline and incidence waves of the 10/66 surveys in Peru, Mexico, and China, while in Nigeria we will supplement the baseline survey with a new incidence wave before implementing the INDEP study protocol. We will then use an incident case–control design, sampling within the well-characterised 10/66 survey samples to identify four groups of interest (see below) for more detailed household interview. The qualitative component will comprise a series of detailed household case studies comprising multiple key informant interviews and participant observation. Household selection will be guided by prior hypotheses and emerging data. We will also collect contextual data on relevant national policies, welfare and healthcare financing, and background information about study catchment areas including local health facilities and other relevant resources. This work will be based upon desk-based research: access to web-based resources such as policy documents, newspaper archives and national and regional government records. These data will be particularly pertinent in determining the impact of the external policy environment, including the reach of social protection and health services.
The study will be based in 10/66 survey catchment areas in four countries; China, Peru, Mexico and Nigeria. At the baseline of the 10/66 survey, the Peru sites comprised urban catchment areas (1381 older people sampled in Lima Cercado and San Miguel in the capital city, Lima) and rural sites (n = 552 in Cerro Azul, Imperial, Nuevo Imperial, Quilmana, San Luis, San Vicente in Canete coastal province). In Mexico we also sampled urban (n = 1003 in six districts in Tlalpan, Mexico City) and rural (n = 1000 in nine villages in Morelos, a mountainous district 70 km from Mexico City) catchment areas. The urban site in China was Xicheng, close to Tiananmen Square (n = 1160), while the rural site comprised 14 villages in Daxing, a rural district 40 kilometres away (n = 1002). In Nigeria we sampled 1132 older people in seven mainly rural communities in Dunukofia, Anambra State.
Selected households and participants
We defined care dependence as the needs for care that arise from difficulties in performing important tasks and activities related to daily living. These difficulties commonly occur among older people due to the interacting effects of multiple health problems: chronic physical conditions that affect different organ systems as well as co-morbid mental and cognitive disorders. Care needs of older people were ascertained at three time-points (baseline and incidence surveys and during the INDEP study interview). Data from baseline and incidence survey was used to categorise households in to the following three groups. Interviewers asked the person selected as a key informant even open-ended questions (what kind of help does X need inside of the home?; what kind of help does X need inside of the home?; who, in the family, is available to care for x?; what help do you provide?; do you help to organise care and support for x?; is there anyone else in the family who is also involved in helping?; what help do they provide?; what about friends and neighbours?; what help do they provide?) followed by an interviewer coding that the older person does not need care; needs care occasionally; or needs care much of the time. This judgment is further guided by an assessment of critical intervals of care; what do you think would be the longest period of time that X could manage by themselves, without help from others, supposing that they were living on their own? Those households where the older person(s) were categorised as “needs care much of the time” were those defined as incident/chronic care households (see definitions below). Key informants were selected by interviewers on the basis of who knew the older person best and who would be able to give the clearest and most detailed account of current circumstances and were usually co-resident or other family members.
Incident care households (where all older residents were independent at baseline, but in which one or more have become care dependent by the incidence survey).
Chronic care households (households containing one or more care dependent older people at baseline, who remained care dependent in the incidence survey).
Control households (where all older residents were independent at baseline, and remained so at the incidence survey).
All households meeting criteria for incident or chronic care were selected for inclusion in the INDEP study. In each site, control households equivalent in number to the sum of incident and chronic care households were selected in each site, at random from all those eligible, and batch matched to care households for the age of the oldest resident.
The designation of some care and control households will change, based upon changed circumstances since the last 10/66 (follow-up) survey. Where all index older people needing care have died (incident or chronic care households) the household will be re-designated as a ‘care exit’ household. Where all index older people have died in a control household, the household will be excluded from the study. Where index older people have moved to another physical location they will be followed up to the new household, and the change of location and household composition will be recorded.
Quantitative research methodology
For each selected household, we aim to conduct a household interview with a suitably qualified key informant (usually the self-defined head of household), brief interviews with each of the surviving index older people, and an informant interview for each older person to provide an independent perspective on their health and needs for care. The detailed household interviews are to be conducted masked to the household group status. Masking will not be possible in Nigeria, in which setting we will conduct incidence phase interviews selecting all incident and chronic care households, and every fourth control household for the INDEP study.
Household interviews for household income, consumption and assets have not been used in previous waves of the 10/66 survey. The questions for the INDEP study were developed from questionnaires used successfully in community research into social pensions, poverty and wellbeing in South Africa and Brazil (Lloyd-Sherlock et al. 2012). We further checked in a preparatory meeting with local investigators the relevance and comprehensiveness of questions regarding sources of income and types of expenditure, and adjusted the phrasing of questions for each country to reflect the local systems.
Interviews were piloted in local settings. The primary aim of piloting was to assess the acceptability of the length of interviews. Length of household interviews was variable (depending on number of household members) but was generally found to be acceptable. Minor changes to syntax were made in response to piloting and in some cases additional clarifications were added to ensure that the meaning of questions reflected that agreed upon in the preparatory meeting.
The detailed household interview comprises:
A household assets index covering household goods and amenities (telephone or mobile phone, stove, electricity supply, television, radio or stereo, refrigerator, sewing machine, bicycle, computer, and motor vehicles), and ownership of land, property and livestock.
Assets in savings or investments (bank or savings account, stocks or shares)
Total monthly equivalent net household income, calculated by ascertaining the amounts and sources of all regular incomes (20 items), and the identity of recipients. Total income will be divided by the modified OECD equivalence scale (1.0 for the first adult, 0.5 for all other adults, and 0.3 for children) to account for economies of scale.
Consumption, 25 items eliciting food consumption (the value or cost of all food consumed at home and outside of the home), household expenses and other personal expenditure (Angelini et al. 2008), also divided by the OECD equivalence scale. For each expenditure item we enquire whether this is about the same, more, less or much less than in a typical month one year previously.
Out of pocket expenditure on all health and home care services in the last three months, for each household member.
Household debt and loans, and other indicators of financial strain. These included; asking for help from friends or relatives, an employer, a religious organisation, or charity; borrowing from a bank, moneylender or loan shark; cutting down on food consumption; trying to find extra work; running up an account with a shop; applying for a grant; apply for food parcels or vouchers; drawing on savings, selling stocks or shares; any other action to address the financial difficulty.
Subjective assessment of overall financial status; How would you rate the financial situation of this household at present? Is it very good, good, average, bad or very bad? How would you rate the financial situation of the household compared to three years ago? Is it better, the same or worse than three years ago?
Household composition and roles
Current household composition, and all changes since baseline interview (with reference to household composition recorded at that time).
Current economic activity of all household members (full-time education, full or part-time employment/nature of occupation, seeking work, disabled, retired, homemaker), reasons for not being in paid work (including providing care to children or older household residents) and changes in status since baseline interview.
Health status of all household residents, needs for care arising from long-term illness or disability, and the identity of the main caregiver for all residents needing care.
The main purpose of the brief interview with each index older person is to update information on their health status since the last 10/66 survey, through self-reported health and disability (World Health Organisation Disability Assessment Scale (WHODAS 2.0) (WHO 2010). We also collect information on personal income, intergenerational reciprocity (gifts or transfers of money to other household members, and care or supervision of children or others), decision-making autonomy, needs (comfort and shelter, food, medical care, clothes and other necessities of daily life) met and unmet, and life satisfaction. If the index older person lacks capacity to provide this information we conduct the interview with a suitably qualified proxy informant.
The main purpose of the interview with a suitably qualified key informant for each older person is to assess their current needs for care. The interview is based upon the methods used in the 10/66 surveys, as outlined previously in the description of the selection of households for the INDEP study. In the INDEP study, we will look at the content of the care needs in more detail. For those older people requiring care, we enquire about the daily time spent assisting with communication, transport, dressing, eating, grooming, toileting, bathing, and general supervision. We also establish the identities of all household residents providing care for the older person, and whether they had stopped education or work to provide care.
We will use multi-level mixed effects analyses (residents nested within households) to test the hypotheses that, controlling for baseline household composition and assets:
Incident and chronic care households have lower annual equivalised net household incomes and lower total food consumption than control or care exit households
Children (aged 15 and under) who were resident at baseline in chronic and incident dependence households are less likely to have completed secondary education (12 years) and will have completed fewer total years of education than children in control households
Out-of-pocket healthcare and homecare costs will be higher in incident and chronic care households than control or care exit households
That effects 1 to 3 above are mediated by levels of disability and total person hours of care and supervision required by older residents
That effects 1–3 above will be modified by household size (larger households being better placed to absorb shocks), the age of the main carer (smaller effects when the carer is aged 65 or over), and by indicators of social protection (pensions, cash transfers from outside of the household, health insurance)
Quantitative analysis will also be used to explore factors associated with particular patterns of household care allocation. Inter alia, these will include household factors (e.g. household composition, socio-economic status), those related to the dependent older person (e.g. sex, pension status and other income, relationship to household head) and those relating to the main carer (e.g. employment status, age, relationship to care-recipient). Particular attention will be given to factors associated with use of paid care by non-family members.
Power analysis suggests that we will have 90% power (at 95% confidence) to detect small to medium effect sizes (0.47 to 0.65) on e.g. consumption, income and healthcare expenditure when comparing dependent and control households where, as for most sites, the numbers of household in each group ranges between 100 and 250. For Nigeria, where numbers of households in each group are likely to be smaller, between 55 and 70 households in each group would permit detection of moderate to large effect sizes, (0.78 to 0.89) at 90% power or (0.66 to 0.77) at 80% power.
We will analyse data from completed questionnaires only. Experience from other 10/66 studies suggests that the level of missing data within otherwise complete questionnaires is likely to be low. We will analyses reasons for non-completion of interviews using data from baseline and incidence questionnaires.
Qualitative research methodology
Case study households (approx six per site) will be purposively sampled from the quantitative survey. Control households will not be included in the qualitative analysis. For each household, interviews will be conducted separately with several key informants including dependent older people (where feasible), the main carer, any other household or non-household members identified as playing a significant role in caring for the dependent older person, the household head and other key decision makers. This will yield a set of detailed and comprehensive household case studies nested within the larger quantitative study.
Guidance for qualitative interviews was developed iteratively. Following early pilot interviews carried out in Peru, it was decided that interviews will be done in a narrative style, allowing interviewees to “tell a story” about the older person’s care needs, the impact of this upon the household and how the household has coped with these changes. Experiences from pilot interviews in Peru suggested that this interviewing style would elicit the richest data due to the close resemblance of the interviews to how participants might discuss their experiences about the onset of dependency outside of the context of the study. Interviewers will be asked to make notes about key events, so that they are then able to ask about decision-making and changes to household finances related to these events. Interviewers will also complete a family tree, mapping the key relationships within and outside of the household.
The development of the qualitative methodologies has been iterative and informed by initial qualitative and quantitative data as well as interviewer’s early experiences of pilot interviews. The qualitative team met in London in May 2013 to discuss emerging themes from pilot data (by this time, interviews with at least one household in each country had been carried out) and to plan the main phase of data collection. The following key household characteristics were identified as being of particular interest in relation to the initial research questions.
Chronic poverty i.e. households with few economic resources wherein this situation has been long-term rather than short-term
Incident poverty i.e. short-term reduction in economic wealth, often due to illness, jobloss, household changes
Large households i.e. those with extended families living in the same household
Small households i.e. where older people live alone or with a spouse only
Households with substantial difficulties i.e. substance abuse, debt, violence
Households that seem to be coping well with the challenges of dependency and/or economic poverty
Households where there is more than one dependent person i.e. older person + others who need substantial care- young children, others with disability
Other households that stand out/were memorable for some reason
Criteria were selected after consideration of the INDEP themes and research questions, discussions of emergent findings from pilot interviews and meeting with members of staff from HelpAge International and ADI (carried out 13th-17th June, 2013, London).
It was also decided to optimise the mixed methods structure of the INDEP study by gathering further background data from the quantitative teams by carrying out focus group discussions. Quantitative teams were asked to discuss households that particularly stood out in relation to the key characteristics identified from pilot data. This data will be used in combination with quantitative datasets to identify households for interview in the main phase of qualitative data collection.
Although based upon iteratively developed topic guides, interviews will be receptive to other considerations that informants consider to be significant. Data will be fully transcribed and translated, and then managed in NVivo7. Analysis will be informed by the initial research questions, but will be strongly inductive since a key aim is to explore informants’ own perceptions of and explanations for responses to incident dependence. The anonymised data sets will be archived in the Economic and Social Data Service.
Project resources and training
Field work in each country is led by a research coordinator, with quantitative interviews (household and older person interviews) conducted by a team of four to six appropriately trained local research assistants. After initial tracing of the index older persons (defining a household as control, incident or chronic care) the research assistant (blinded to household status) contacts the research coordinator for unblinded advice as to how to proceed.
Questionnaire data from the household and older person interviews is checked for completeness, and then double data entered on to specially developed EPIDATA data entry systems, including range and consistency checks. All qualitative data from open-ended interviews is recorded on digital audio recorders, transcribed in the local language (generally Spanish, Mandarin or Igbo), and then translated into English.
The INDEP study protocol has been approved by King’s College London Research Ethics Committee and relevant local authorities in each study site. It is to be expected that a significant proportion of the older people who are potential participants in the study will currently have dementia. We will use an approach similar to that used previously in 10/66 studies: if the older person lacks capacity to consent, the next of kin will be asked to provide signed assent. Participation will be subject to the older person not showing signs of distress or dissent when the information sheet is read to them. For each household, the index older person or persons are first approached for consent for an individual and informant interview, and to nominate a suitable key informant for the household interview. If they do not consent, the household is excluded.