Table 2.

The probability that a clinical wound observation is related to the presence of biofilm^†

	Binomial test
		Category	N	Observed prop.	Test prop.	Exact Sig. (two‐tailed)
Presence of slough	Group 1	Yes	38	0·58	0·50	0·215
	Group 2	No	27	0·42
	Total		65	1·00
XS Exudate	Group 1	No	5	0·08	0·50	0·000*
	Group 2	Yes*	60	0·92
	Total		65	1·00
Poor tissue quality	Group 1	No	29	0·45	0·50	0·457
	Group 2	Yes	36	0·55
	Total		65	1·00
Signs of pyocyanin	Group 1	No*	52	0·80	0·50	0·000*
	Group 2	Yes	13	0·20
	Total		65	1·00
Gelatin Wound Surface	Group 1	No*	46	0·71	0·50	0·001*
	Group 2	Yes	19	0·29
	Total		65	1·00
Gelatin Reforms Quickly	Group 1	No*	53	0·82	0·50	0·000*
	Group 2	Yes	12	0·18
	Total		65	1·00

^* P value < 0·05.

^†The binominal probability questions asked here is a yes or no response. Therefore, statistical significance should be denoted by an * if the visual marker is accurate in detecting biofilm. The benchmark was set at 50% occurrence rate for the visual marker to be present. The results below indicate that visual markers (with exception of XS exudate) are no better than chance alone.