Skip to main content

Table 4 Descriptive statistics of hole shape using image analysis

From: Assessing bed net damage: comparisons of three measurement methods for estimating the size, shape, and distribution of holes on bed nets

Size groupa (diameter in cm) N Circularity Aspect ratio
Mean Std. dev. Median 25th percentile 75th percentile
Smaller than 0.5 cm < 0.5 cmb 274 0.53 0.28 1.3 0.25 1.7
Smaller than thumb (0.5 ≤ diameter ≤ 2.0 cm) 3147 0.46 0.16 2.4 1.9 3.2
Larger than thumb, smaller than fist (2.0 < diameter ≤ 10.0 cm) 1005 0.35 0.14 3.5 2.4 4.9
Larger than fist, smaller than head (10.0 < diameter ≤ 25.0 cm) 180 0.28 0.14 4.8 3.7 6.9
Larger than head (diameter > 25.0 cm) 83 0.25 0.15 5.5 4.3 7.5
Total (all holes) 4689 0.43 0.18 2.6 1.9 3.7
  1. Circularity indicates the amount of elongation of the hole (1 indicates a perfect circle, values closer to 0 indicate more elongation). Aspect ratio is the ratio of the major axis to the minor axis
  2. aDiameter was approximated as the length of the major axis
  3. bNot measured with the World Health Organization Pesticide Evaluation Scheme (WHOPES) guidelines