Table 4.
Rating of reported validity and reliability for foot posture measures and definition of flexible flat foot in paediatric populations
| Foot posture measure | Study code | Flat foot definition used | Age range of participants in years | Validity as reported in paediatric population | Reliability as reported in paediatric population | Rating of validity/reliability (Yes/No/With caution) |
|
|---|---|---|---|---|---|---|---|
| Plain film radiograph angles | Calcaneal pitch | [33, 53] | < 20° | 4–6 & 8–13 | Nil | Nil | No/No |
| [38] | < 23° | 4–18 | Nil | Nil | No/No | ||
| [31] | ≤ 15.4° | 7–12 | NR [57] | Nil | No/No | ||
| AP talocalcaneal | [53] | > 25° | 4–6 | Nil | Nil | No/No | |
| [33] | > 30° | 8–13 | Nil | Nil | No/No | ||
| Plantarflexion of talus | [53] | > 23° | 4–6 | Nil | Nil | No/No | |
| Lateral talocalcaneal | [33] | > 45° | 8–13 | Nil | Nil | No/No | |
| Calcaneal first metatarsal | [38] | 145°-170° | 4–18 | Nil | Nil | No/No | |
| Talus-first metatarsal | [33] [31] | > 4° | 7–13 | Nil | NR [80], NA [64] | No/No | |
| Foot print indices | Arch index | [35, 54], [36] | ≥ 0.26 | 3–6, 5–13, 4–14 | Nil | Nil | No/No |
| [37] | ≥ 0.26 | 10 | NR [58] | Substantial [81], NR [37] | No/Yes | ||
| [30, 32, 42] | > 0.26 | 6–13 | Nil | Nil | No/No | ||
| Chippaux-Smirak | [46] | ≥ 59% | 6–9 | Nil | Excellent [46] | No/Yes | |
| [34] | > 62.7% | 3–7 | Moderate [34] | NR [65] | With caution/No | ||
| [56] | > 62.7% | 3–7 | Moderate [34] | Nil | With caution/No | ||
| [37], | ≥ 45% | 10 | NR [59] | NR [37] | No/No | ||
| [40] | ≥ 45% | 3–17 | Nil | Nil | No/No | ||
| [31] | ≥ 40% | 9–16 | Moderate [31] NR [60] |
Nil | With caution/No | ||
| Clarke’s angle | [34] | ≤ 14.04 | 3–6 | Moderate [34] | Nil | With caution/No | |
| [37] | ≤ 20° | 10 | Nil | NR [37, 59] | No/No | ||
| [38] | < 42° | 9–16 | Excellent [38] | Nil | With caution/No | ||
| [55] | < 42° | 4–18 | Nil | Nil | No/No | ||
| [31] | < 29.9° | 9–16 | Moderate [31],NR [60] | Nil | With caution/No | ||
| Staheli arch index | [46] | ≥ 1.28 | 6–9 | Nil | Excellent [46] | No/Yes | |
| [34] | > 1.07 | 3–6 | Moderate [34] | NR [65] | With caution/No | ||
| [48] | > 1.15 | 6–10 | NR [59, 61] | Nil | No/No | ||
| [52] | > 0.89 | 10–12 | Nil | Nil | No/No | ||
| Footprint index | [42] | < 0.25 | 9–12 | Nil | Nil | No/No | |
| Martirosov’s K index | [37] | ≥ 1.25 | 10 | Nil | NR [37] | No/No | |
| Footprint evaluation | [51] | X > Y | 6–17 | Nil | NR [66] | No/No | |
| Instep | [45] | 100 mm | 6–12 | Nil | Nil | No/No | |
| Plantar footprint | [49] | ≥ 50% | 4–13 | Nil | Nil | No/No | |
| Static foot measures | Rearfoot eversion | [53] | > 10° | 4–6 | Nil | Nil | No/No |
| [33] | ≥ 4° | 8–13 | Nil | Nil | No/No | ||
| [47] | ≥ 4° | 6–13 | Nil | NA [67] | No/No | ||
| [55] | > 5° | 4–18 | Nil | Nil | No/No | ||
| [39] | > 5° | 3–6 | Nil | NR [68] | No/No | ||
| [41] | > (7° - age) | 3–6 | Nil | Substantial [41] | No/Yes | ||
| Arch Height Index | [47] | ≤ 0.37 | 6–13 | NR [62] | Substantial [47]NR [82, 83] | No/Yes | |
| [50] | < 0.31 | 8–15 | Nil | Nil | No/No | ||
| FPI-6 | [29] | ≥ + 6 | 3–15 | Not rated^ [63] | Substantial [69] | With caution/Yes | |
| [28] | ≥ + 4 | 6–11 | Nil | Excellent [70] | No/Yes | ||
| Navicular height | [42] | < 20 mm | 9–12 | Nil | Nil | No/No | |
| Other measures | Plantar pressure analysis (FGP) | [53] | 54% | 4–6 | Nil | Nil | No/No |
AP – anterioposterior, FPI-6 – foot posture index – 6 item version, NR – not reported in cited text, NA – not available, FGP – foot ground pressure
Notes: See data management for ratings of reliability and validity. *See Additional file 1 for rating parametres. ^RASCH analysis