Table 5.

PPV of positive synovial fluid (SF) culture combined with synovial fluid (SF) cell count/differential (95% CI)

All sites
	PPV of positive cultures/positive SF cell count/differential	p valuea	PPV of positive cultures/ negative SF cell count/differential	p valuea
All staphylococci	86% (74 to 94)	0.36	42% (17 to 70)	0.01
Staphylococcus aureus	90% (71 to 98)	1	100% (22 to 100)	1
S. epidermidis	77% (57 to 91)	1	33% (2 to 87)	0.17
S. lugdunensis	100% (61 to 100)	1	100% (5 to 100)	1
Other staphylococci	100% (22 to 100)	0.47	17% (1 to 59)	0.33
Hip
All staphylococci	86% (66 to 96)	0.42	50% (18 to 82)	0.19
S. aureus	88% (52 to 99)	1	100% (22 to 100)	1
S. epidermidis	78% (44 to 96)	1	50% (3 to 98)	0.43
S. lugdunensis	100% (37 to 100)	1
Other staphylococci	100% (5 to 100)	1	25% (1 to 76)	0.58
Knee
All staphylococci	86% (70 to 96)	0.74	25% (1 to 76)	0.04
S. aureus	92% (65 to 100)	1
S. epidermidis	77% (49 to 94)	1
S. lugdunensis	100% (37 to 100)	1	100% (5 to 100)	1
Other staphylococci	100% (5 to 100)	1

^aComparison with PPV of positive cultures alone.