Table 6.

Reliability of the four fear of falling rating scales

Rating scale	Cronbach’s alpha (time 1)	ICC (95% CI)	đ(95% CI) a	SEM (% of possible scoring range) b	SDD (% of possible scoring range) c
FES-I	0.96	0.92 (0.88–0.95) n = 81	–0.05 (–1.09–0.99)	3.4 (7)	9.6 (20)
FES(S)	0.98	0.82 (0.73–0.88) n = 76	–2.17 (–6.95–2.61)	15.4 (12)	42.7 (33)
ABC	0.98	0.86 (0.79–0.91) n = 68	–0.04 (–3.68–3.60)	11.0 (11)	30.5 (30)
mSAFFE	0.94	0.85 (0.78–0.90) n = 76	0.76 (–0.19–1.72)	3.0 (9)	8.4 (24)

FES-I = Falls Efficacy Scale-International, FES(S) = Swedish Falls Efficacy Scale, ABC = Activities-specific Balance Confidence scale, mSAFFE = modified Survey of Activities and Fear of Falling in the Elderly, ICC = intraclass correlation coefficient (one-way random model, absolute agreement, single measures), SEM = standard error of measurement, SDD = smallest detectable difference.

^ađ defined as mean difference in scale scores (time 2 − time 1).

^bSEM defined as ${\mathrm{SD}}_{\mathrm{baseline}}\times \sqrt{1-\mathrm{ICC}}$.

^cSDD defined as $\mathrm{SEM}\times 1.96\times \sqrt{2}$.