Fieldwork Process

Data Collection Mode

The vast majority of the data were collected though face-to-face interviews. While telephone interviews and assisted interviews were conducted to ensure a high response rate, they are only used as a last resort. Table 33 provides the proportion of people interviewed by telephone in all five waves. Due to the fact that some households moved outside of the 488 areas originally selected across Australia in wave 1 and the desire to interview as many people as possible, more telephone interviews are necessary in later waves. The overall incidence of telephone interviews has increased from 0.3 in wave 1 to 6.5 per cent in wave 5.

Table 47: Proportion of respondents interviewed by telephone (%)

Timeline

The interviews are conducted annually with the interviewer briefing occurring in mid–August each year. In wave 1, all but a few interviews were completed by December 2001. From wave 2 onwards, the fieldwork has been extended by several months into the following year to focus on tracking and interviewing hard–to–find cases.

Table 48 provides details of the fieldwork dates and Table 49 shows how the individual interviews are spread across each fieldwork period. For those interviewed in the next wave, most are interviewed within one month of the anniversary of the previous interview (as shown inTable 50). Up to 4 per cent of the interviews are, however, conducted more than three months before or after the anniversary of the interview in the previous wave.

Table 48: Fieldwork dates and proportion of interviews post Dec 2004

Table 49: Distribution of individual interviews by month, waves 2 to 6

Table 50: Time between interview dates and anniversary of previous wave interview, waves 2 to 6

Survey Notification Material

In wave 1, the selected households were sent a primary approach letter and a brochure approximately one week prior to when the interviewer was scheduled to make contact with the household. This pre-interview material marketed the survey to respondents as a study about ‘Living in Australia’ and, among other things, emphasised that participation was voluntary and provided a means for sample members to opt out of the survey prior to an interviewer calling.

From wave 2 onwards, a primary approach letter and newsletter were sent to the last known address of the households approximately one month prior to when the interviewer was scheduled to make contact with the household. The newsletter provides respondents with some results from the previous wave. In addition to the posted pre–interview material, households with people who had not been part of the household in the previous wave were given a New Entrants Brochure. This brochure provided more information about the purpose of the study, why they had been asked to participate, and a method to opt out of the study if they chose to. A follow–up newsletter has also been introduced from wave 3 onwards.

A copy of the primary approach letters, brochures and newsletters are available from the HILDA website: http://www.melbourneinstitute.com/hilda/doc/doc_respinfo.htm.

Respondent Incentives

From wave 5, individuals responding with an interview received $25 and a $25 bonus was received by each fully responding household (i.e., each eligible member if the household provided an interview). This cash incentive structure is different to the one used in earlier waves.

Previously, in waves 1 to 4, a $50 cash incentive was offered to households where all eligible household members completed the Person Questionnaire. If this did not occur, a $20 payment was offered to households if at least one interview was obtained.

The availability of this new incentive was made clear in both primary approach letter and the brochure/newsletter.

Call Routine, Follow–Up and Refusal Aversion

In wave 1, the fieldwork was conducted in two stages. The first stage involved the interviewer working in an area over a three–week period. They visited each selected household according to the specified call–back pattern.⁴⁴ This achieved approximately 65 per cent of the interviews from each area. The remainder of each workload was then consolidated into intensive follow-up workloads and reassigned to the most experienced interviewers. They again visited each of these households according to the specified call–back pattern. These interviewers obtained the remaining 35 per cent of the interviews from each area.

From wave 2 onwards, a tracking component is incorporated into the fieldwork, splitting it into three distinct periods.⁴⁵ All households were issued into the field for the first stage, and where all the interviews had not been completed, they were reissued into the field in the next period.⁴⁶ If a household could not be found at either one of these stages, they were put into tracking and once found were issued back into the current stage if found quickly or more generally into a later period. The period stage was used to finalise households that had to be traced and could not be immediately issued back into the field and also to contact some households where it was deemed beneficial to contact them in the third time (for example, a household member may have been away from the household at earlier contacts or they may have been temporarily unwell or busy).

Foreign Language Interviews

Language difficulties between the interviewer and the potential respondent were most often resolved by another member of the household acting as an interpreter. However, a small number of interviews each wave are conducted with a professional interpreter present during the interview.

Interviewer Monitoring

Several methods were used to ensure the fieldwork quality was consistent and maintained throughout the fieldwork collection period. These methods focused on the training, experience, in-field checking and monitoring of the interviewers.⁴⁷

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