Ethical clearance was obtained from the Institutional Review Board (IRB), College of Health sciences, Addis Ababa University (AAU), Ethiopia. Permission to use the EORTC QLQ-C30 questionnaire tool was secured from the EORTC. Patients were individually approached and informed about the purpose of the study; written consent was then obtained to confirm their willingness to participate. Patients were also assured that the completed questionnaires will not be stored in the patient’s clinical record and will remain confidential.

The study was conducted in the Departments of Gynecology and Obstetrics and Radiotherapy of TASH. TASH is a teaching hospital located in Addis Ababa, the capital city of Ethiopia, and it provides both teaching and clinical care services in different fields. It is also a major referral center from all corners of the country, especially for cancer patients. The Clinical Oncology Department is the only center in the country providing radiation therapy.

A facility based cross-sectional study was conducted from January 1 to June 30, 2014.The sample size (n) required for the study was calculated using the formula to estimate a single population using a coefficient of variation. The coefficient of variation for EORTC QLQ-C30 GHS showed a CV of 0.30 which was considered for sample size calculation[12]: In this study we assumed, 95% confidence level, 5% of absolute precision, the final sample size was calculated based on the formula n=[(zα2)2(CV)2d2]n=[(1.96)2(0.3)20.052]=138.29=139

By considering the 10% non-response rate, the total sample size was 153 gynaecological cancer patients. All patients who came to the specified departments during the study period and fulfilled the inclusion criteria were included in the study until the sample size was achieved. Totally 140 gynecological cancer patients were included in the analysis. A total of 13 patients were excluded from the analysis because they were not interested to be included in the study. This study had included patients with age 18 years and older who are treated for the first time for gynaecological cancer. Patients who had previously received cancer treatment were excluded from the study, as were, patients with psychiatric disorders, communication disorders, other severe medical illnesses, coexisting malignancies, and positive HIV sero-status.

The Amharic version of EORTC QOL-C30 is composed of 30 questions. Of the 30 items, 24 are organized into nine scales: Physical functioning (5 items; questions from 1 to 5), Role functioning(2 items; question 6 and 7), Emotional functioning(4 items; questions from 21 to 24), Cognitive functioning(2 items; question 20 and 25), Social functioning(2 items; question 26 and 27), GHS/quality of life(2 items; question 29 and 30), Fatigue(3 items; questions 10, 12 and 18), Nausea and vomiting(2 items; question 14 and 15), and Pain(2 items; question 9 and 19) and 6 single items assessing financial impact and various physical symptoms such as dyspnea, insomnia, appetite loss, constipation and diarrhea(questions 28, 8, 11, 13, 16 and 17 respectively[13]).

The row scores were transformed to 0 to 100 based on the recommended formulas in the scoring manual for each EORTC QLQ-C30 component [14]. A high score for a functional scale represents a high/healthy level of functioning whereas a high score for a symptom scale or item represents a high level of symptomatology or problems [13]. The translation of the EORTC QLQ-C30 into Amharic version was made by another previous project. This study had received the translated Amharic EORTC QLQ-C30 from EORTC with grant to use for the proposed study.

Data was checked for completeness and consistency, cleaned, coded, and entered to SPSS version 20 windows. Descriptive statistics and independent t-test were employed.

The internal consistency of EORTCQLQ-C30 measured by the Cronbach’s α coefficient for each domain. The Cronbach’s α value higher than 0.7 is generally considered to be satisfactory[14]. Stepwise multivariable linear regression model was fitted to identify the most determinative components of EORTCQLQ-C30 against Global health status (Criterion validity). The standardized regression coefficient was reported with p values p< 0.05 considered statistically significant. Multi-trait scaling analysis was used to test the convergent and item discriminant validity of the EORTC QLQ-C30. Convergent validity was revealed if the item domain correlation was ≥ 0.40[15, 16], while the requirements for discriminant validity were satisfied if the value of correlation coefficients between the item and its own domain was higher than other domains[16]. Known-groups validity was evaluated by comparing groups with a clinically evident difference using an independent t-test.

A total of 140 patients in whom a diagnosis of a single entity of gynaecologic cancer is suspected or confirmed were included in the analysis. The mean (SD) age for the participants was 53.06(12.45) years. Of the total 140 participants 68.5% have never gone to school. With respect to marital status 52.9% of participants are currently on marriage while the rest of the study participants were not (i.e. divorced, widowed or single). Majority of participants come from outside Addis Ababa. Most of the participants (62.1%) were housewives (Table 1)

The internal consistency of the Amharic version of EORTC QLQ-C30 had a Cronbach’s α value of 0.81. All of the domains have an acceptable internal consistency except for cognitive function domain with Cronbach’s α = 0.29 (Table 2).

Most of the correlation between inter domain scales of EORTC QLQC-30 was found statistically significant. Insomnia, loss of appetite, pain, fatigue, financial difficulties, and constipation were significantly negatively correlated with all of the functional domain components and GHS (p<0.001). Nausea and vomiting were negatively correlated with all functional domains (physical, social, emotional, and role function) and GHS except cognitive function (p<0.05). Diarrhea was not significantly correlated with any of the functional domain and GHS, p>0.05 (Table 3).

All the components of EORTC QLQ-C30 were modeled against the GHS score via stepwise linear regression model. The results showed that emotional functioning (p<0.001), fatigue (p<0.001), and social functioning (p = 0.004) were the determinative scales of QLQ-C30 on GHS (Table 4).

Known-groups validity was evaluated based on different treatment types. This study assumed that patients receiving surgery would report a better QOL as compared to patients receiving radiation. Generally speaking, cervical cancer patients at an earlier stage can be treated by surgery and those at a late stage are treated by radiation. Thus, we selected two subgroups among cervical cancer patients, a surgery group (56 cases) and a radiation group (84 cases), and compared the mean QOL scores between the two groups by t-tests. There were significant differences for twelve out of 15 domains (Table 5).

The convergent validity, which is measured by correlations between the item and its own domain, was not acceptable for most of the domains, except for fatigue, role function, and GHS. The physical function domain did not meet discriminant validity criterion except in item 3. Physical function items correlated more strongly with fatigue domain than its own domain. All items of emotional function, role function, fatigue, and GHS meets the discriminant validity criterion. Item 9, 19, 25, and 26 did not meet the discriminant validity criterion (Table 6).