A cross sectional study.

The study was conducted in Makerere University, the largest public University in Uganda located about 2 km north of Kampala City with a student population of 39,546, 44% (17,400) being females as of 2017, specifically in Makerere University College of health sciences. The college of health sciences has school of medicine, school of biomedical sciences, school of health sciences and the school of public health, and has a diverse population of students from all over the country as well as international students that makes it a representative sample population. Female undergraduate students who consented to the study were included while those on hormonal contraception or those who were pregnant or lactating were excluded from the study.

The sample size obtained using the Kish Leslie (1965) formula basing on a previous study in Nigeria by Amu & Bamidele, 2014 was 265, assuming withdrawal of consent or incomplete data of 10%, we aimed at a minimum of 265/0.9 = 295, thus a sample size of 295 was used. Study participants were selected by consecutive sampling of available female undergraduate students in Makerere University College of health sciences.

Data was collected using a pre-tested self-administered questionnaire from a population of female undergraduate students at Makerere University College of health sciences who enrolled for the study having met the eligibility criteria. The questionnaire contained questions on sociodemographic characteristics such as age, course, year of study, number of pregnancies, education sponsor, etc. menstrual characteristics such as presence or absence of menstruation, age at menarche, length of cycles, regularity of cycles, presence or absence of painful menstrual, duration of menstruation, number of sanitary pads used each menstruation to quantify the amount of bleeding, the severity of menstrual pain (mild, moderate, severe), premenstrual symptoms and participants’ perception of menstrual pain based on their experience were collected. Menstrual disorders were defined as follows: Normal menstrual frequency was defined as menstrual cycles repeated about once every 24–38 days, regular menstrual cycle referred to cycles in which the shortest to longest cycle variation is ≤ 9 days, irregular menstrual cycle referred to cycles in which the shortest to longest cycle variation is ≥ 10 days, infrequent menstruation referred to a menstrual cycle repeated about once every > 38 days, frequent menstruation referred to a menstrual cycle repeated once every < 24 days, intermenstrual bleeding referred to bleeding between cyclically regular onset of menses, dysmenorrhea referred to painful menstruation, premenstrual symptoms were symptoms preceding menses and resolving with onset of menses and included painful breast on touching, difficulty concentrating, mood changes and depression, primary amenorrhea referred to no menses by age 16 years, secondary amenorrhea referred to no menses for an interval of time equivalent to a total of at least three months in students who had menstruated previously.

QOL was measured using the WHO QOL BREF (Field trial version) [15] which comprises of 4 domains; physical, psychological, social and environmental. Physical domain measures activities of daily living, dependence on medicinal substances and medical aids, energy and fatigue, mobility, pain and discomfort, sleep and rest, and work capacity; psychological domain measures bodily image and appearance, negative feelings, positive feelings, self-esteem, spirituality/religion/personal beliefs, thinking, learning, memory, and concentration; social domain measures personal relationships, social support, and sexual activity; environmental domain measures financial resources, freedom, physical safety and security, health and social care: accessibility and quality, home environment, opportunities for acquiring new information and skills, participation in and opportunities for recreation/leisure activities, physical environment, and transport. The scores for each domain being scaled in a positive direction from 0–100.

The WHOQOL-BREF [15] produced a quality of life profile from which four domain scores were derived. The four domain scores that denote an individual’s perception of quality of life in each particular domain were scaled in a positive direction (i.e., higher scores denote higher quality of life). The mean score of items within each domain was used to calculate the domain score. Mean scores were then multiplied by 4 in order to make domain scores comparable with the scores used in the WHOQOL -100. The first transformation method converted the domain scores to range between 4–20, comparable with the WHOQOL-100. The second transformation method converted domain scores to a 0–100 scale. Where more than 20% of data was missing from an assessment, the assessment was discarded. Where an item was missing, the mean of other items in the domain was substituted. Where more than two items were missing from the domain, the domain score was not calculated (with the exception of domain 3, where the domain would only be calculated if ≤ 1 item is missing).

Pretesting questionnaire was done by collecting data from a set of 30 students who were not part of the final study participants and the questionnaire was found to be appropriate. The WHO QOL BREF has been validated in multiple studies as a tool for measuring QOL [16, 17] and we used it without any modification in this study and this part of the questionnaire was not pretested. Participants were physically approached by the study team immediately after classes/lectures/ward rounds during normal working hours on working days and briefed about the study. Eligible students who were willing to participate were given consent forms to fill. Research assistants gave pretested questionnaires to all eligible undergraduate students in Makerere University College of health sciences who accepted and consented to the study. The filled questionnaires were collected on the same day, assembled at a designated point and cross-checked for any errors. The participants were accorded privacy while entering their information.

The research assistants were trained on the research protocol, ethical issues and data collection procedures. Completed questionnaires were double-checked for completeness and accuracy and stored under key and lock by the principal investigator who was also the only person with permission to access the data for confidentiality purposes. There was double entry of data into EPIDATA manager version 4.6.0 and the two entries compared and contrasted to eliminate errors in data entry. Data cleaning to ensure consistency and data integrity was done before export to STATA version 14.1 (Stata Corp, college Station, Texas, USA).

Participant characteristics such as age, menarche, were described using percentages, frequencies, tables, medians and their interquartile range. The prevalence of menstrual disorders was calculated and presented as proportions. The domains of the QOL BREF were summarized using means and 95% confidence intervals because the data were normally distributed. ANOVA test and t-test were used to establish the relationship between the reported menstrual characteristics and the mean domain scores in the QOL BREF, P < 0.05 was considered statistically significant. The mean domain scores of QOL in participants with menstrual disorders were compared with those without. The strength of the associations between menstrual disorders and QOL was tested using Cohen’s d effect size calculated as the difference in means divided by pooled standard deviation. Cohen’s d > 0.25 was considered to indicate practical Independent variables were dysmenorrhea, premenstrual symptoms, heavy menstrual flow, amenorrhea, frequent menstruation, irregular menstruation, intermenstrual bleeding, infrequent menstruation while the dependent variables were the quality-of-life Domains in the WHO QOL BREF i.e., physical, psychological, social and environmental domains.

Informed consent was obtained from participants and only those who agreed by signing in the consent form were recruited in the study. Protocol was handed to the department of obstetrics and gynecology Makerere University for review after which it was forwarded to the Makerere University School of medicine research and ethics committee (SOMREC) for approval (approval number: REC REF 2020–122). Copies of permission letters and attached copies of the protocol were distributed to the principle of the Makerere University College of health sciences seeking his permission to collect data. Participation in the study was completely voluntary and participants were free to withdraw from the study any time they wished. Information obtained from the participants were kept confidential and anonymous by assigning code numbers for participants’ questionnaires that were used on all research notes and documents and keeping questionnaires and any other identifying participant information in a locked file cabinet in the personal possession of the researcher.