Table 4.

Summary of Hierarchical Regressions for Testing the Incremental Validity of the PAAS

	Independent variables	Betaa	R2	R2 change	F change	p
Outcome measure: HADS depression subscaleb
Step 1	BPI – Pain Intensityc	0.34	0.12	0.12	40.0	<0.001
	Age	−0.07
Step 2	PAASc	0.63	0.40	0.28	277.0	<0.001
Outcome measure: HADS anxiety subscaleb
Step 1	BPI – Pain Intensityc	0.18	0.07	0.07	23.41	<0.001
	Age	−0.21
Step 2	PAASc	0.31	0.14	0.07	47.00	<0.001
Outcome measure: BPI pain interference subscaleb
Step 1	BPI – Pain Intensityc	0.62	0.65	0.65	268.64	<0.001
	Age	0.02
	HADS - Anxietyb	0.00
	HADS - Depressionb	0.35
Step 2	PAASc	0.32	0.70	0.05	98.24	<0.001

Note. PAAS = Penn Arthralgia Aging Scale; BPI = Brief Pain Inventory; HADS = Hospital Anxiety and Depression Scale.

^aBetas reported are those from the step at which the variable was entered.

^bSquare-root transformed.

^cLog-transformed.