The Data
Interviews
For the first three waves of PATH, interviews were conducted by trained interviewers, usually in participant’s homes. To provide a high level of confidentiality, participants complete most of the interview (e.g. self reported health, substance use, personality and psychosocial measures) themselves using a computer with a touch sensitive screen. However a number of physical (eg FEV, grip strength) and cognitive tests (eg memory, reaction time) are administered by the interviewer. Cheek swabs were collected at the baseline interview for the extraction of DNA for genetic analysis.
In 2011, with the commencement of the fourth wave, our funding did not allow for face-to-face interviews with the majority of the 20+ cohort. Participants were invited to complete an online version of the questionnaire. A subgroup of local participants were also invited to have a short face-to-face interview that included some cognitive and physical testing.
Data collection
Each wave of data collection takes place over three years, with the young, midlife and older cohorts interviewed over consecutive years. Participants are asked to complete an interview online (or in some cases by phone, or on paper) with trained interviewers conducting face-to-face interviews with those located in the ACT/Queanbeyan area, and travelling to other centres. Those currently living overseas are asked to complete an interview online.
This sample diagram below shows the number of participants in each cohort with dates of assessment.
Analysis of PATH data
In addition to the sub-studies aligned with PATH, researchers from other organisations worldwide have collaborated on the analysis of de-identified PATH project data. In order to analyse PATH data it is necessary to develop a collaboration with one or more of the PATH investigative team and have the research approved by the PATH Governance Committee. There are guidelines on the use of PATH data to ensure all research is conducted ethically, to a high standard and falls within the aims of the PATH project. The PATH Governance Committee also approve all papers published using PATH data.
Results from physical testing
Some participants like to be able to compare their performance on the physical tests. Results from the four waves of interviewing are shown below for each age group. At Wave 4 physical testing was not performed for the entire cohort.
Note: FEV = Expired volume in 1 second (litres), FVC = Full lung volume (litres).
20+ age group
| First Interview (1999/2000) | Second Interview (2003/2004) | Third Interview (2007/2008) | Fourth Interview (2011/2012) | |||||
|---|---|---|---|---|---|---|---|---|
| Test | Females | Males | Females | Males | Females | Males | Females | Males |
| Handgrip | 29 | 47 | 30 | 48 | 31 | 52 | 31 | 52 |
| FEV/FVC (height <160 cm) |
2.7/3.0 | 3.4/3.7 | 2.7/3.1 | 3.1/4.1 | 2.7/3.2 | 4.1/5.0 | 2.8/3.3 | N/A |
| FEV/FVC (height 160‑169 cm) |
3.0/3.3 | 3.3/3.9 | 3.0/3.4 | 3.4/4.0 | 3.0/3.5 | 3.4/4.2 | 3.0/3.6 | 3.8/4.4 |
| FEV/FVC (height 170‑179 cm) |
3.2/3.6 | 4.0/4.5 | 3.2/3.7 | 4.0/4.6 | 3.3/3.9 | 4.1/4.7 | 3.3/4.0 | 4.3/5.0 |
| FEV/FVC (height ≥180 cm) |
3.6/4.0 | 4.4/5.0 | 3.7/4.1 | 4.4/5.1 | 3.6/4.2 | 4.4/5.2 | 3.7/4.6 | 4.5/5.4 |
| Blood pressure (systolic/diastolic) |
112/72 | 129/76 | 110/72 | 127/77 | 116/73 | 131/76 | 119/76 | 134/79 |
| Pulse | 72 | 68 | 71 | 68 | 72 | 68 | 75 | 71 |
40+ age group
| First Interview (2000/2001) | Second Interview (2004/2005) | Third Interview (2008/2009) | Fourth Interview (2011/2012) | |||||
|---|---|---|---|---|---|---|---|---|
| Test | Females | Males | Females | Males | Females | Males | Females | Males |
| Handgrip | 29 | 47 | 28 | 48 | 28 | 48 | 28 | 47 |
| FEV/FVC (height <160 cm) |
2.4/2.8 | 3.3/3.9 | 2.3/2.7 | 3.0/3.6 | 2.3/2.8 | 3.3/3.9 | 2.3/2.8 | 3.4/3.8 |
| FEV/FVC (height 160‑169 cm) |
2.7/3.2 | 3.1/3.6 | 2.6/3.1 | 3.1/3.6 | 2.6/3.2 | 3.1/3.7 | 2.5/3.1 | 3.0/3.7 |
| FEV/FVC (height 170‑179 cm) |
3.0/3.5 | 3.5/4.1 | 2.9/3.4 | 3.4/4.1 | 2.9/3.5 | 3.4/4.2 | 2.8/3.5 | 3.4/4.2 |
| FEV/FVC (height ≥180 cm) |
3.3/3.9 | 3.9/4.7 | 3.2/3.7 | 3.8/4.6 | 3.1/3.7 | 3.9/4.7 | 3.0/3.8 | 3.8/4.7 |
| Blood pressure (systolic/diastolic) |
118/77 | 132/84 | 119/78 | 131/84 | 128/79 | 135/83 | 126/78 | 134/82 |
| Pulse | 72 | 71 | 71 | 71 | 71 | 70 | 72 | 71 |
60+ age group
| First Interview (2001/2002) | Second Interview (2005/2006) | Third Interview (2009/2010) | Fourth Interview (2011/2012) | |||||
|---|---|---|---|---|---|---|---|---|
| Test | Females | Males | Females | Males | Females | Males | Females | Males |
| Handgrip | 25 | 42 | 23 | 38 | 22 | 40 | 22 | 36 |
| FEV/FVC (height <160 cm) |
1.8/2.3 | 2.6/3.0 | 1.8/2.2 | 2.6/3.2 | 1.8/2.2 | 2.5/2.9 | 1.6/2.1 | 2.6/3.2 |
| FEV/FVC (height 160‑169 cm) |
2.0/2.6 | 2.4/3.1 | 2.0/2.5 | 2.4/3.0 | 2.0/2.5 | 2.4/3.1 | 1.8/2.4 | 2.2/2.9 |
| FEV/FVC (height 170‑179 cm) |
2.2/2.8 | 2.8/3.5 | 2.1/2.7 | 2.7/3.4 | 2.1/2.7 | 2.7/3.5 | 1.9/2.5 | 2.6/3.3 |
| FEV/FVC (height ≥180 cm) |
2.5/2.9 | 3.1/3.9 | 2.2/2.9 | 3.0/3.8 | 2.4/3.0 | 3.0/3.9 | 2.1/2.7 | 2.8/3.7 |
| Blood pressure (systolic/diastolic) |
136/80 | 143/86 | 134/79 | 142/83 | 144/78 | 147/81 | 140/74 | 141/76 |
| Pulse | 72 | 71 | 71 | 68 | 71 | 67 | 69 | 66 |