J Hematol

Journal of Hematology, ISSN 1927-1212 print, 1927-1220 online, Open Access

Article copyright, the authors; Journal compilation copyright, J Hematol and Elmer Press Inc

Journal website http://www.thejh.org

Original Article

Volume 2, Number 1, June 2013, pages 22-26

Plateletcrit as a Screening Tool for Detection of Platelet Quantitative Disorders

Figures

Figure 1. ROC for thrombocytopenia.

Figure 2. ROC for thrombocytosis.

Tables

**Table 1.** Comparison of the Three Groups
Variable	Number	Platelet count × 10⁹/L	Pct %	MPV fl	PDW %
Thrombocytopenia	106	72.5	0.09	12.42	63.8
Normal platelet	82	269.3	0.23	9.13	56.6
Thrombocytosis	18	606	0.50	8.3	49.3

**Table 2.** Pct Cut Off Values With Positive and Negative Cases for Thrombocytopenia
Cut off Pct value %	True positive	True negative	False positive	False negative	Sensitivity	Specificity
0.01 - 0.10	1	101	0	104	0.9	100
0.11 - 0.21	68	100	0	38	64	100
0.22 - 0.32	105	65	35	1	99	65
0.33 - 0.43	106	28	72	0	100	28
0.44 - 0.54	106	12	88	0	100	12
0.55 - 0.65	106	6	94	0	100	6
0.66 - 0.76	106	2	98	0	100	2

**Table 3.** Pct Cut Off Values With Positive and Negative Cases for Thrombocytosis
Cut off Pct value %	True positive	True negative	False positive	False negative	Sensitivity	Specificity
0.66 - 0.76	0	190	0	16	0	100
0.55 - 0.65	1	189	0	16	5	100
0.44 - 0.54	6	189	0	11	35	100
0.33 - 0.43	12	189	0	5	70	100
0.22 - 0.32	17	179	10	0	100	94
0.11 - 0.21	17	141	48	0	100	74
0.01 - 0.10	17	68	121	0	100	35

**Table 4.** Truth Table for Thrombocytopenia at Plateletcrit Below 0.20%
Variable	Thrombocytopenia absent	Thrombocytopenia present
Positive	20	101
Negative	82	3

**Table 5.** Truth Table for Thrombocytosis at Plateletcrit Above 0.36%
Variable	Thrombocytosis absent	Thrombocytosis present
Positive	3	17
Negative	185	1

**Table 6.** Comparison With Other Studies
Studies	Giovanetti 2011	Wiwanitkit 2004	Adibi 2007	Naina north east 2010	Naina south India 2010	Our study
Number	306	215	19923	-	-	206, 106 thrombocytopenia, 82 normal, 18 thrombocytosis
MPV fl	9.6 males 9.89 females	12.79	9.2	13.1	7.35	Thrombocytopenia- 12.42 Normal- 9.13 Thrombocytosis- 8.3
Pct %	0.24 males 0.28 females	0.24	0.22	0.17	0.19	Thrombocytopenia- 0.09 Normal- 0.23 Thrombocytosis- 0.50
PDW	17.42 fl males 17.30 fl females	46.79%	46.95%	17.4 fl	16.38 fl	Thrombocytopenia- 63.8% Normal- 56.6% Thrombocytosis- 49.3%