Sample Collection and analysis

Electronic questionnaires were administered to participating women to collect socio-demographics, sexual history, STI history, antibiotic/antifungal drug use. Vaginal swab sample was collected either by health worker or self-collection depending on the participant’s choice. Chlamydia testing was conducted by the principal investigator using Chlamydia Rapid Test Device, a rapid immunoassay test manufactured by Quingdo Hightop Biotech Co., Ltd. Shandong, 266112, China. The test had an in-built procedural control. Known positive and negative control samples (supplied with each kit) were run concurrently with test samples.

With the help of trained health personnel, the participants were provided with gloves and directed to a private room with a stool. She undressed to expose only the vaginal area and got in a comfortable position (putting one leg on a stool) for self-collection procedure. A vaginal swab was collected using a sterile plastic shaft cotton-tipped swab stick. The swab was inserted into the vaginal canal ensuring most of the tip was not seen. The swab was firmly rotated for 15–20 seconds and then withdrawn from the vaginal canal. The swab was immersed into the mixing tube and capped, and then handed over to the investigator. The same procedure was applied when the health provider collected the sample.