Table 2.

Mean Values for Staffing Patterns and Patient Volume across VA Primary Care Practices—1996, 1999 (Standard deviation presented within parentheses.)

	1996	1999
Primary care (PC) patients per VAMC	9,160 (4,251)	12,481 (5,621)**
Numbers of clinicians per PC practice by type
Nurse practitioners (NPs)†	2.0 (1.0)	3.2 (0.8)**
Physicians‡	8.3 (2.2)	8.9 (2.0)
Physician assistants (PAs)‡	1.2 (2.5)	1.4 (2.5)
PC clinicians (NPs, physicians, PAs)‡	12.6 (2.0)	14.5 (1.8)**
Rates of clinicians per PC practice by type
NPs/10,000 PC patients†	2.2 (1.0)	2.7 (0.7)
Physicians/10,000 PC patients‡	10.0 (2.0)	7.9 (1.8)**
PAs/10,000 PC patients‡	1.4 (2.8)	1.2 (2.5)
PC clinicians/10,000 PC patients‡	15.1 (1.7)	12.9 (1.5)**
NP-per-physician ratio†	0.2 (0.1)	0.4 (0.1)**

^**1999 mean is statistically different compared to 1996 mean (p <.05)

^†Square-root transformation of the variable was performed to achieve approximate normality

^‡Logarithmic transformation of the variable was performed to achieve approximate normality

Note: On the transformed variables, the means are based on initially transforming the data, performing the calculations on the transformed results, and then reversing the transformation to obtain the values presented in the table