Table 1 Audit of available data sources and assessment of data quality
Data Source | Data Set | Methodological Soundness | Accessibility | Accuracy and Reliability |
|---|---|---|---|---|
Australian Bureau of Statistics (ABS) | Census [19] Population-level data on socioeconomic variables and demographics for a variety of geographic regions | Snapshot of Australian general population | Data collected every 5 years and freely available Most recent census data for 2011 | Self-reported data Main sources of error: respondent error (self-enumerated), partial or non-response, processing error Quality management procedures applied to reduce error |
Department of Human Services (DHS) | Health Care Card data [20] National data collected by the government welfare agency ‘Centrelink’ of adults and children issued a low income ‘Health Care Card’ which provides access to health care and related benefits, including lower costs. | General Australian population | Routinely collected data available by geographic location | Administrative records data |
Australian Institute of Health and Welfare (AIHW); and AIHW Dental Statistics and Research Unit (DSRU) | National Health Workforce Data Set (NHWDS) [21] Combines data from the National Registration and Accreditation Scheme (NRAS) with data collected from the Dental Workforce Survey (DWS) | All registered dental practitioners | Available data for 2011 and 2012 Access restricted to statistical reports by AIHW | Registration data together with survey data In deriving estimates two sources of non-response to survey are accounted for: item non-response and survey non-response |
Australian Cancer Database (ACD) [18] Data collection of all primary, malignant cancers diagnosed in Australia since 1982. The ACD is compiled at the AIHW from cancer data provided by state and territory cancer registries through the Australasian Association of Cancer Registries. These registries receive information on cancer diagnoses from a variety of sources such as hospitals, pathology laboratories, radiotherapy centres | Population –based cancer registered patient data in Australia | Data released in AIHW publications and available as interactive data AIHW can also make available a broad range of cancer statistics subject to scientific/ethical review process | Weighted estimates Clinical data based on medical diagnosis | |
National Hospital Morbidity Database (NHMD) [22] Compiled from data supplied by the State and Territory health authorities. It is an electronic collection of records for separations (episodes of care) in public and private hospitals in Australia. It contains demographic, administrative and length of stay data and data on diagnoses of the patient and medical procedures. | Representative general population level data for all separations of admitted patients from all public and private national hospitals | Ongoing collection Statistical reports by AIHW Data requests subject to ethics approvals | Clinical data based on medical diagnosis Extensive validation of data Data are checked for valid values, logical and historical consistency | |
National Survey of Adult Oral Health (NSAOH) 2004-2006 [15] A descriptive ‘snapshot’ of oral health in the adult population of Australia. Random sample of the general population residing in all Australian states and territories. Information is collected using interviews and standardised dental examinations. The survey aims to describe levels of oral disease, perceptions of oral health and patterns of dental care within a representative cross-section of adults across Australia. | General population 15+ years old Sample size: 2267 Response rate: 44 % of sampled population Three-stage stratified sampling design Oral examination restricted to dentate population (N = 1181; 50 % of eligible) | Incidental data Access restricted to statistical reports by AIHW/DSRU | Self-reported oral health status data and clinical data (dentate population) Computer assisted interviews, structured questionnaires pilot tested, trained interviewers Reporting bias Sampling weights applied | |
National Dental Telephone Interview Survey (NDTIS) [16] Telephone survey of a random sample of the Australian population. Respondents include users and non-users of dental services and people eligible and not eligible for public-funded dental care. NDTIS collects basic features of oral health and dental care within the Australian population, including access to services. There is no clinical component to the survey. Survey aims to: collect oral health and dental care data within the Australian population; monitor the extent of social inequalities within the dental sector; investigate the underlying reasons behind dental behaviours, and the consequences of these behaviours. | General population 5+ years old. Two-stage stratified sample design. Sample size varies between surveys. | Every 2 ½ years Access Restricted to statistical reports by AIHW/DSRU | Self-reported survey data Computer assisted interviews, structured questionnaires pilot tested, trained interviewers Reporting bias Sampling weights applied | |
Child Dental Health Survey (CDHS) [16] The Survey monitors the dental health of children enrolled in school and community dental services operated by the health departments or authorities of State and Territory governments. Survey aims to: examine the distribution of oral health status by geographic location and demographic factors, and the identification of high-risk groups; and examine changes in oral health status among children over time | Random sample of children 4–15 years old enrolled in the school dental services Sample size varies between surveys | Annual data collection Data available for Victoria up to 2004 Access restricted to statistical reports by AIHW/DSRU | Routine clinical examination data. Inter/intra examiner reliability not assessed Data cleaning processes to correct data entry errors and eliminate duplicate cases Sampling weights applied | |
Child Oral Health Study (COHS) 2002-2004 [17] A Survey of parents of children from South Australia, Victoria, Tasmania and Queensland | Random sample of children aged between 5 and 15 | Incidental data Access restricted to statistical reports by AIHW/DSRU | Retrospective reporting Recall bias Data weighted to the age, sex and estimated resident populations | |
Longitudinal Survey of Dentists’ Practice Activity (LSDPA) [23] A survey of Australian dentists that report on services provided in private dental practice. LSDPA data were used to estimate the mean services and cost of services for each visit reported in NDTIS. | Random sample of dentists from the dental register surveyed at five-year intervals. Response rate 70 % + at all five waves. Sample supplementation procedure provided representative cross-sectional sample | Five yearly-survey commenced in 1983–84 and completed in 2009–10 Statistical reports by DSRU/AIHW | Mailed structured self-completed questionnaires Validation study indicated representative estimates Weighted estimates | |
National Dental Labour Force Data Collection (NLFDC) [24] The National Dental Labour Force Survey collects information on the demographic and employment characteristics of dental practitioners in Australia. Data comes from the National Registration and Accreditation Scheme (NRAS) and optional Dental Workforce Survey | All dental practitioners registered in Australia at the time of the survey | Response rates vary between years and States Significant delays between data collection and release of statistics Most recent reports in 2006 and 2009 | Item on-response and survey non-response Data are weighted to account for the population being examined and imputed for non-response questions | |
Cancer Council Victoria (CCV) | Victorian Cancer Registry (VCR) [34] Population-based cancer registry receiving information on cancer diagnoses from 240 hospitals, 30 pathology laboratories and cancer screening services in Victoria | All cancer diagnosis in Victorian residents | Online summary statistics (incidence and mortality) by type of cancer, age, sex, year of diagnosis, region of residence Data can also be requested (conditions and limitations apply) | Clinical data based on medical diagnosis |
Cancer Council Victoria (CCV)/Dental Health Service Victoria (DHSV) | Oral Health Policy Data [35, 36] As part of a larger review of health promotion policy CCV conducted a review of oral health municipal promotion plans. Policy and program data was collected by CCV for a project in partnership with DHSV by context analysis of the policies documents which local governments use for promoting the health of their constituents | All local government planning documents across Victoria | Most available data for 2009 Data provided by CCV | Content Analysis |
Dental Health Services Victoria (DHSV) | Workforce Dataset [37] Dataset includes the number and type of staff at all community dental clinics in Victoria. | Data is collected at clinic level (all public dental clinics in the State) | DHSV and agency workforce data readily available monthly. | DHSV workforce calculated from the DHSV payroll database Agency workforce data is self-reported by agencies |
Oral Health Promotion Program [38] Smiles 4 Miles is an Oral Health Promotion Program developed by DHSV and is targeted at preschoolers. The data collected is the proportion of kindergartens in a given community implementing the program. | Random sample of kindergartens across Victoria | Data is available from 2009 onwards | Data only represents the number of kindergartens in each region | |
Distance to the closest public dental clinic [39] Distance will be calculated using the Victorian census collection districts (CCDs) map. Each CCD will be represented by its centroids which will be imported into a statistical software programme. The distance will be then calculated using the great circle metric. | Distance will be calculated using ‘crow file’ metric which does not take into consideration the ways which patients visit community clinics | |||
Department of Families, Housing, Community Services and Indigenous Affairs (FaHCSIA), Australian Institute of Family Studies (AIFS), Australian Bureau of Statistics (ABS) | Longitudinal Study of Australian Children (LSAC) [25] Longitudinal study following the development of children and families from all Australia. It commenced in 2004 with two cohorts of children. First wave of data collection in 2004 with subsequent main waves every two years The study aimed to investigate the contribution of children’s social, economic and cultural environments to their adjustment and wellbeing | National representative longitudinal sample Cross-sequential design with two cohorts (N = 5000 each): 0–1 years and 4–5 years at the commencement of the study Two-stage random clustered design Stratification was used to ensure proportionate number of selected children to the total numbers of children within each state/territory | Accessible data Baseline collection in 2004 and final wave commenced in 2009/2010 | Different data collection methods between waves Computer based self-complete questionnaires Sample weights produced to reduce selection bias and participant non-response, validated scales appropriate to children’s age |
Victorian Department of Health and Human Services (DHHS) | Victorian Admitted Episodes Dataset (VAED) [40] Episodes of care level morbidity data on all admitted patients from Victorian public and private hospitals including rehabilitation centres, extended care facilities and day procedure centres. The VAED also contains demographic, administrative and length of stay data and data on diagnoses of the patient and medical procedures. | Representative general population level data for all separations of admitted patients from all Victorian public and private hospitals | Ongoing collection Data available after request to the department | Clinical data based on medical diagnosis Extensive validation of data Data are checked for valid values, logical and historical consistency |
Victorian Population Health Survey (VPHS) [27] The VPHS collects information via computer assisted telephone interviews (CATI) at the State, regional and local government levels on health outcomes, determinants and behavioural risk factors of adult Victorians aged 18 years and over | Representative random sample of population aged 18+ residing in Victoria Participation rates vary between years | Annually Accessible data by financial year | Survey data is weighted | |
Community Water Fluoridation Program [41] Water fluoridation is the adjustment of the natural amount of fluoride in the water supply to a level recommended for optimal dental health benefits. Some communities in regional and rural Victoria without optimal water receive carefully controlled amounts of fluoride in their drinking water. | Community access to a fluoridated water supply. Coverage is classified geographically by postcode | Accessible data | ||
Titanium database [26] The Titanium database is an electronic patient record management system for public dental agencies. It contains administrative, demographic, clinical, oral health and risk factors data. | Eligible population level data only. Eligible is set by government policy and is targeted to populations at highest risk of poor oral health. | Routinely collected Accessible by DHSV staff for all public dental agencies in Victoria | Clinical examination data User data entry error Most common identified areas of inaccuracy include: - Capture of DMF score where dental chart has not been performed or is incomplete - Un-erupted teeth incorrectly recorded as missing inflating the M component of the DMFT score Identification of teeth missing and filled for reasons not due to dental decay | |
Victorian Department of Education and Training (DET) | Victorian Child Health and Wellbeing Survey (VCHWS) [28] State-wide survey of children 0–13 years of age. The survey is conducted to examine the health of Victorian children and to describe the general health levels and high risk groups. Data is collected on health outcomes, socioeconomic determinants, and behavioural risk factors | Population level cross-sectional survey N = 5000, response rate: 86.6 % | Repeated every three years | Parental self-reported data Interviewer training Monitoring and call-back validation Structured questionnaires Existing scales with proven reliability and validity |
School Entrant Health Questionnaire (SEHQ) [29] State-wide survey undertaken when children are in their first year of schooling. The SEHQ contains a range of questions focusing on family demographics, child health and development. The questionnaire is linked to School Nursing program | Population-based level cross-sectional survey of all children entering primary schools | Repeated annually | Parental self-reported data Structured, piloted questionnaire School nurse clinical assessment Existing scales with proven reliability and validity |