Table 2.
Results of reliability, test–retest and systematic differences of the Spanish Podiatry Health Questionnaire (PHQ-S) according to each domain.
| PHQ-S | Test n = 52 |
Retest n = 52 |
Reliability Test | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Domain | Mean ± SD (CI 95%) † |
Item–Total Correlation | α if Item Removed | Mean ± SD (CI 95%)† |
Item–Total Correlation | α if Item Removed | ICC (IC 95%) | p-Value * | SEM | %SEM | MDC | %CV |
| Walking | 1.71 ± 0.66 (1.52–1.89) |
0.81 ** | 0.75 | 1.71 ± 0.66 (1.52–1.89) |
0.83 ** | 0.76 | 0.93 (0.87–0.96) |
1.000 | 0.00 | 0.00 | 0.00 | 0.00 |
| Hygiene | 1.21 ± 0.49 (1.07–1.35) |
0.73 ** | 0.769 | 1.23 ± 0.50 (1.09–1.36) |
0.72 ** | 0.79 | 0.93 (0.88–0.96) |
0.317 | 0.00 | 0.30 | 0.01 | 1.15 |
| Nail care | 1.50 ± 0.64 (1.32–1.67) |
0.67 ** | 0.79 | 1.53 ± 0.69 (1.34–1.73) |
0.66 ** | 0.81 | 0.93 (0.88–0.96) |
0.414 | 0.00 | 0.36 | 0.01 | 1.40 |
| Foot pain | 1.94 ± 0.69 (1.75–2.12) |
0.81 ** | 0.757 | 1.96 ± 0.63 (1.79–2.13) |
0.77 ** | 0.78 | 0.91 (0.85–0.95) |
0.705 | 0.00 | 0.21 | 0.01 | 0.72 |
| Worry and concern | 1.73 ± 0.71 (1.53–1.93) |
0.50 ** | 0.84 | 1.69 ± 0.61 (1.52–1.86) |
0.58 ** | 0.83 | 0.90 (0.83–0.94) |
0.480 | 0.00 | 0.50 | 0.02 | 1.65 |
| Quality of life | 1.55 ± 0.66 (1.37–1.74) |
0.75 ** | 0.77 | 1.61 ± 0.69 (1.42–1.80) |
0.78 ** | 0.78 | 0.871 (0.775–0.92) |
0.366 | 0.01 | 0.96 | 0.04 | 2.68 |
| Total | 9.85 ± 2.7 (9.11–10.59) |
N/A | N/A | 9.87 ± 2.75 (9.13–10.61) |
N/A | N/A | 0.99 (0.96–0.98) |
0.567 | 0.00 | 0.00 | 0.00 | 0.14 |
| Total Cronbach α test: 0.81 | Total Cronbach α retest: 0.82 | |||||||||||
| VAS | 6.31 ± 2.56 (5.60–7.03) |
−0.50 ** | 6.34 ± 2.22 (5.72–6.96) |
−0.39 ** | 0.86 (0.77–0.91) |
0.834 | 0.03 | 0.54 | 0.09 | 1.46 | ||
Abbreviations: SD, standard deviation; CI 95%, confidence interval of 95%; CV, coefficient of variation; ICC, intraclass correlation coefficient; N/A, not applicable; * Wilcoxon signed-rank test; ** p-value < 0.001 (in bold); † values are expressed as lower–upper limits of the 95% confidence interval.