Box counting serial image index (BCSI) versus point counting serial image index (PCSI) in scoring melasma: A comparative, non-interventional validation study

Background Point counting serial image index (PCSI) is a scoring method used to assess the area and severity of melasma. Double tracing and the inability to assess scattered pigmentation are its limitations. Objectives To propose modifications to PCSI, the Box counting serial image index (BCSI) was compared and validated with PCSI. Methods In BCSI, a preset grid was placed, and serial images were captured. One speck of pigmentation was counted as one box. The area involved and time taken were recorded by the principal investigator and coinvestigator using BCSI and PCSI methods, respectively. The intensity of the pigmentation was recorded on a scale of 0-5. Melasma score = Area x Intensity of pigmentation. The difference in the total scores and time taken were analysed. Results A significant decrease (p<0.0003) in the total scores between baseline and first follow-up and baseline and second follow-up was observed in both methods. Similarly to PCSI, BCSI was found to be sensitive to changes over time with treatment (p<0.0003). These p values were recalculated using Bonferroni corrections. The mean time taken by PCSI was significantly higher than BCSI (p < 0.0003). Limitations Grid placement over bony prominences and interference of facial hair. Conclusion BCSI overcomes the limitations of PCSI by directly capturing images and it is easy and rapid.