Integration of patient characteristics and the results of Chlamydia antibody testing and hysterosalpingography in the diagnosis of tubal pathology: an individual patient data meta-analysis

Tubal patency tests are routinely performed in the diagnostic work-up of subfertile patients, but it is unknown whether these diagnostic tests add value beyond the information obtained by medical history taking and findings at physical examination. We used individual patient data meta-analysis to assess this question. We approached authors of primary studies for data sets containing information on patient characteristics and results from tubal patency tests, such as Chlamydia antibody test (CAT), hysterosalpingography (HSG) and laparoscopy. We used logistic regression to create models that predict tubal pathology from medical history and physical examination alone, as well as models in which the results of tubal patency tests are integrated in the patient characteristics model. Laparoscopy was considered to be the reference test. We obtained data from four studies reporting on 4883 women. The duration of subfertility, number of previous pregnancies and a history of previous pelvic inflammatory disease (PID), pelvic surgery or Chlamydia infection qualified for the patient characteristics model. This model showed an area under the receiver operating characteristic curve (AUC) of 0.63 [95 confidence interval (CI) 0.610.65]. For any tubal pathology, the addition of HSG significantly improved the predictive performance to an AUC of 0.74 (95 CI 0.730.76) (P 0.001). For bilateral tubal pathology, the addition of both CAT and HSG increased the predictive performance to an AUC of 0.76 (95 CI 0.740.79). In the work-up for subfertile couples, the combination of patient characteristics with CAT and HSG results gives the best diagnostic performance for the diagnosis of bilateral tubal pathology.