ToolsCalculators
Reid's Colposcopic Index (RCI)
Grades a cervical lesion seen at colposcopy to predict low- vs high-grade histology.
Reid's Colposcopic Index (RCI)
Lesion margin
Colour
Vessels
Iodine (Lugol's/Schiller's) staining
Result0 points
Colposcopic pattern most consistent with a low-grade lesion (CIN 1).
- Margin
- 0
- Colour
- 0
- Vessels
- 0
- Iodine staining
- 0
When to use
- Grading the most abnormal area of a cervical lesion at colposcopy to estimate the likelihood of high-grade CIN before biopsy.
- Standardising documentation of colposcopic impression across four morphologic features.
Formula
RCI = margin score (0-2) + colour score (0-2) + vessel pattern score (0-2) + iodine staining score (0-2). Range 0-8; higher scores favour higher-grade disease.
Pearls and pitfalls
- Developed and validated before HPV testing and digital colposcopy; used today mainly as a teaching framework for structured lesion description.
- Colposcopic impression, including RCI, does not replace histologic confirmation by biopsy.