Table 3.
Sample size by measure and participant group
| Construct | Measure | Children | Parents | Parent–child pairs | 2019 Data release | ||
| n=1874 | All n=1874 | Biological n=1854 | All n=1874 | Biological n=1854 | |||
| Anthropometry | Height, weight | 1873 (99.9) | 1865 (99.5) | 1845 (98.5) | 1864 (99.5) | 1844 (98.4) | ● |
| Body composition* | 1859 (99.2) | 1844 (98.4) | 1824 (97.3) | 1837 (98.0) | 1817 (97.0) | ● | |
| Pubertal status | Puberty Development, Sexual Maturity scales | 1807 (96.4) | – | – | – | – | ● |
| Menstruation† | 844 (45.0) | 1610 (85.9) | 1598 (85.3) | 740 (39.5) | 733 (39.1) | ● | |
| Modified Comprehensive Acne Severity Scale | 1762 (94.0) | – | – | – | – | ● | |
| Bone, muscle | Peripheral quantitative CT | 1271 (67.8) | 1250 (66.7) | 1240 (66.2) | 1231 (65.7) | 1222 (65.2) | ● |
| Cardiovascular | Carotid intima-media thickness | 1489 (79.5) | 1476 (78.8) | 1463 (78.1) | 1462 (78.0) | 1449 (77.3) | ● |
| Pulse wave velocity, pulse wave analysis | 1836 (98.0) | 1790 (95.5) | 1773 (94.6) | 1769 (94.4) | 1752 (93.5) | ● | |
| Blood pressure | 1777 (94.8) | 1749 (93.3) | 1732 (92.4) | 1682 (89.8) | 1666 (88.9) | ● | |
| Microvascular structure (retinal photography) | 1307 (69.7) | 1317 (70.3) | 1307 (69.7) | 1292 (68.9) | 1282 (68.4) | ||
| Respiratory | Spirometry | 1759 (93.9) | 1774 (94.7) | 1754 (93.6) | 1688 (90.1) | 1668 (89.0) | ● |
| Language | Expressive and receptive language (Recall' Sent) | 1441 (76.9) | 1446 (77.2) | 1433 (76.5) | 1415 (75.5) | 1402 (74.8) | ● |
| Receptive vocabulary (NPVT) | 1443 (77.0) | 1457 (77.7) | 1444 (77.1) | 1401 (74.8) | 1389 (74.1) | ● | |
| Hearing | Pure tone audiometry | 1488 (79.4) | 1493 (79.7) | 1480 (79.0) | 1480 (79.0) | 1467 (78.3) | ● |
| Tympanometry | 1099 (58.6) | 1101 (58.8) | 1092 (58.3) | 1065 (56.8) | 1056 (56.4) | ● | |
| Speech reception threshold (LiSN-S) | 1483 (79.1) | 1482 (79.1) | 1469 (78.4) | 1466 (78.2) | 1453 (77.5) | ● | |
| Diet and food choices | National Secondary Students’ Diet and Activity | 1846 (98.5) | 1862 (99.4) | 1846 (98.5) | 1837 (98.0) | 1821 (97.2) | ● |
| Snack observation | 1294 (69.1) | 1246 (66.5) | 1235 (65.9) | 1205 (64.3) | 1195 (63.8) | ● | |
| Physical activity, time use | Accelerometry | 1382 (73.7) | 1440 (76.8) | 1424 (76.0) | 1223 (65.3) | 1209 (64.5) | ● |
| Time-use diary (MARCA) | 1830 (97.7) | – | – | – | – | ● | |
| Strength and fitness | Eurofit broad jump | 1771 (94.5) | – | – | – | – | ● |
| PWC170 VO2max test | 1301 (69.4) | – | – | – | – | ● | |
| Vision | Freiburg Visual Acuity Test | 1494 (79.7) | 1491 (79.6) | 1478 (78.9) | 1481 (79.0) | 1468 (78.3) | ● |
| 2D and 3D photography | 2D and 3D photos of teeth and tongue | 1486 (79.3) | 1480 (79.0) | 1467 (78.3) | 1478 (78.9) | 1465 (78.2) | |
| 3D photos of face | 1331 (71.0) | 1316 (70.2) | 1305 (69.6) | 1313 (70.1) | 1302 (69.5) | ||
| Handwriting, written language | Handwritten story about life at age 25 | 1811 (96.6) | – | – | – | – | |
| General well-being | ISCW and PedsQL General Well-Being | 1860 (99.3) | – | – | – | – | ● |
| Health-related quality of life | PedsQL, Child Health Utility 9D, AQoL-8D‡ | 1854 (98.9) | 1871 (99.8) | 1853 (98.9) | 1854 (98.9) | 1836 (98.0) | ● |
| Pain | Pain§ | 1586 (84.6) | 1859 (99.2) | 1843 (98.3) | 1576 (84.1) | 1562 (83.4) | ● |
| Natural colouring | Skin, hair and eye colour | 1859 (99.2) | 1859 (99.2) | 1843 (98.3) | 1859 (99.2) | 1843 (98.3) | ● |
| Medications, supplements | Current medications and supplements | 1853 (98.9) | – | – | – | – | ● |
| Health, welfare and community services |
Health service use, hospital admissions | 1874 (100.0) | – | – | – | – | ● |
| Community participation and services | 1822 (97.2) | – | – | – | – | ● | |
| Serum metabolites | NMR metabolomics platform | 1180 (63.0) | 1325 (70.7) | 1313 (70.1) | 1139 (60.8) | 1133 (60.5) | ● |
| Renal function | Urinary albumin and creatinine concentration | 1579 (84.3) | 1671 (89.2) | 1653 (88.2) | 1535 (81.9) | 1518 (81.0) | ● |
| Biological ageing | Telomere length | 1206 (64.4) | 1343 (71.7) | 1330 (71.0) | 1151 (61.4) | 1143 (61.0) | |
Values are n (%) of participants or pairs with data available. These may differ slightly from sample sizes presented in other CheckPoint papers in this BMJ Open Special Issue, where authors have restricted analyses to participants meeting specified levels of data quality or completeness. ’All parents' and ’all parent–child pairs' include biological and non-biological (eg, step, adoptive or biological relatives other than mother or father) parent–child relationships. Parent–child pairs include families where both the child and the parent have data available for that measure.
*381 children and 344 parents have body fat % measured using a two-limb BIA scale at home visits; the remainder have detailed body composition measured using a four-limb BIA scale.
†Girls were asked ’has menstruation started' and ’are you menstruating today?' and women were asked ’are you menstruating today?'
‡Children completed the PedsQL, parents completed the AQoL-8D and both children and parents completed the Child Health Utility 9D.
§Parents completed a subset of the pain questions completed by children.
AQoL-8D, Assessment of Quality of Life 8D; BIA, bioelectrical impedance analysis; ISCW: International Survey of Children’s Well-Being; LiSN-S, Listening in Spatialised Noise–Sentence Test; MARCA, Multimedia Activity Recall for Children and Adults; NMR, nuclear magnetic resonance; NPVT, National Institute of Health Picture Vocabulary Test; PedsQL, Pediatric Quality of Life.