Objectives: To formulate and evaluate the reliability of non-invasive diagnostic scoring system to diagnose endometriosis.

Design: Controlled clinical study.

Setting: Patients attending the Gynaecology and Infertility Clinic of Hospital USM.

Patient(s): Reproductive aged patients with chronic pelvic pain subjected for diagnostic laparoscopic surgery were selected.

Intervention(s): Diagnostic laparoscopic surgery was performed. The presence and stage of endometriosis was determined and tissue biopsy at suspected area of endometriosis was taken. Formation and evaluation of a scoring system was done.

Main Outcome Measure(s): Histology confirmation of endometriosis and endometriosis scoring index.

Result(s): The presence of severe dysmenorrhea, level of serum Ca125 between 50-200 u/ml and the presence of multiloculated ovarian cyst with thick sedimentation were noted to be significantly associated with endometriosis. Subsequently, a scoring index to assess the likelihood of endometriosis was formulated. It is shown that this scoring index, named as CliEndomet, is reliable to detect endometriosis (sensitivity of 0.696, specificity 0.711, PPV=0.78 and NPV=0.614, Kappa coefficient=0.39 at 95% CI, 0.21-0.58; p value ≤ 0.05). It is more capable to detect advanced stage disease than early stage (sensitivity=0.96 versus sensitivity 0.42, 95% CI).

Conclusion(s): CliEndomet scoring system can reliably be used as a diagnostic tool to diagnose endometriosis for patients who refuse to undergo surgical diagnosis and intervention.