The RCAC Scale
The RCAC scale consists of 18 items that constitute six dimensions: Fertility potential, Partner disclosure, Child’s health, Personal health, Acceptance and Becoming pregnant. Each dimension has three items with responses scored on a five-point scale (ranging from 1=Strongly disagree to 5=Strongly agree), with high scores indicate higher levels of reproductive concerns (9).
Swedish translation and cultural adaptation of the Swedish RCAC Scale
For the purpose of use in a study from our research group (12), the original RCAC scale was evaluated for its relevance in measuring fertility concerns in a Swedish context. To achieve this, the scale was forward translated into Swedish based on the two-panel approach and further assessed for cultural adaptation (13). The first step of the cultural adaptation comprised assessment of the appropriateness of the translated scale by one bilingual expert panel and by one lay panel. As a next step, in order to assess if the scale was perceived as relevant and acceptable, focus group discussions and cognitive interviews were performed with representatives of the target population. The process of the cultural adaptation was coordinated by an experienced coordinator to ensure none of the parameters were neglected and to maintain the quality of the adaptation.
Forward translation by bilingual expert panel
The RCAC scale was translated from English to Swedish by two researchers who were native Swedish speakers and well-versed in English. The first translator (T1) had extensive research knowledge in the field of fertility and cancer. The second translator (T2) coordinated the translation and was experienced in instrument translation and adaptation, but was not knowledgeable in the research fields of fertility and cancer. Both researchers had broad experience of clinical work with diverse patient groups. Following individually performed translations of the scale, T1 and T2 discussed discrepancies between the two versions. As a next step, they consulted the principal investigator of the original English version of the RCAC to discuss and clarify the intended conceptual meaning of the scale and specific items. Subsequently, two experts in the field of psychosocial oncology (native Swedish speakers) thoroughly scrutinised both versions and discussed a few remaining issues regarding the translation. As a result, a consensus version of the Swedish version of the RCAC was created. Cultural adaptation included changing the use of “spouse/partner” in the three items of the dimension Partner disclosure to “partner”, as this was deemed more appropriate for use in the Swedish context where it is common for two adults to live together without being married.
Lay panel assessment
For evaluation of the translated version of the scale two lay panels were recruited through personal contacts and local advertisements. The panel members were 3 women and 4 men between 18-41 years old; three had secondary education and four had higher education. Two had children and none of the panel members had been diagnosed with cancer. Panel members were compensated with cinema tickets for their participation. The lay panels were only provided with the Swedish version of the scale, as suggested (13). The lay panel members were instructed to go through all parts of the RCAC scale, including instructions, items and response options. Everyone read each item, then discussed how they perceived the issue and whether there were any alternative translations. Based on the assessment by the lay panels minor changes in wording were made. The main role of the lay panels was to produce a version that was easy to understand for the average Swedish speaking person. The assessment was led by a coordinator who also participated (T2) in the expert panel.
Patient/Target group assessment
The patient/target group included 5 women and 3 men (aged 20-41) who had been treated for cancer. The target group members came from different geographical areas in Sweden and all had secondary or higher education. They evaluated the translated RCAC scale for face validity i.e., if the items and response alternatives were relevant and acceptable. Some concerns were expressed regarding the suitability and relevance of the scale for patients in their late teens, which led us to conducting cognitive interviews as described below. The target group members were compensated for their travel costs and time spent.
Cognitive interviews were performed individually with 3 young individuals (1 female aged 18 years and 2 males aged 17 years) currently being treated for cancer. The participants filled in the Swedish RCAC scale completely themselves and were then interviewed on their experience of filling the form. Following this, the participants were asked to give their input on the individual items in the scale. The most important purpose of the interviews was to ensure that the scale was suitable for teenagers with cancer. Another purpose was to get a final input on the instrument regarding questionnaire structure (including layout and instructions), items and language.
Participants and procedure
A detailed description of the study participants and procedure is presented elsewhere (12). Briefly, a sample of 301 women consecutively diagnosed with invasive breast cancer at age 18-39 years were identified from the Swedish National Quality Register for Breast Cancer. Data collection was conducted by means of a comprehensive postal survey approximately 1.5 years post-diagnosis. Ethical approval for the study was obtained from the Regional Ethical Review Board in Stockholm, Sweden (Ref No: 20131746‐31/4).
The survey completed by the participants comprised several patient reported outcome measures. For the purpose of the psychometric evaluation of the Swedish version of the RCAC, the Emotional Function scale of the EORTC QLQ-C30 version 3.0 (14) and a study-specific item regarding current wish to have (additional) children (response alternatives: Yes, Uncertain, No) were used from the survey.
Statistical analysis was performed using SPSS statistics for Windows, version 24 (IBM Corp., Armonk, N.Y., USA) and IBM® SPSS® Amos, version 25. For all statistical tests, the level of statistical significance was defined as p <0.05.
Construct validity was ascertained using Confirmatory factor analysis (CFA) and convergent validity. CFA was performed to determine the adequacy of the original six-factor of the RCAC on our sample data (9). Missing values for single items (n=15) was handled by imputing the mean of the other two items of the same individual in the same dimension. Those with an entire missing scale (n=7) and those when more than two items in a dimension were missing (n=1) were excluded. Standardized factor loadings and model fit were determined from the CFA. Standardized factor loadings of >0.4 were considered as acceptable as determined from the CFA (15). Model fit was estimated by two absolute indices of overall model fit 1) Root mean square error of approximation ((RMSEA) and 2) Standardized root mean residual ((SRMR) and one relative index of model fit compared to the null model 3) Comparative fit index (CFI). The acceptable thresholds for these indices were defined as RMSEA: 0.05 - 0.08, SRMR: < 0.10 and CFI: > 0.90 according to Kline’s guidelines (16). The degrees of freedom were reported, but were not considered as an indicator of model fit owing to their restrictiveness due to being sensitive to sample size (17). Convergent validity was assessed by calculating the Pearson correlation coefficient for the mean score of the Swedish RCAC scale and the Emotional Function scale of the EORTC QLQ-C30. A moderate magnitude of > 0.3 was considered acceptable (18, 19).
Data quality was assessed using mean scores, standard deviations (SD) and percentages of respondents scoring the minimum (floor) and maximum (ceiling) possible scores were calculated. Floor and ceiling effects were considered present if >15% rated at the lowest (floor) and highest (ceiling) scores (20).
Reliability was assessed by calculating the internal consistency of the six dimensions using Cronbach’s α coefficient. A Cronbach’s α value of >0.70 was regarded as acceptable (21).
Known-groups validity was assessed by comparing groups expected to differ with regard to reproductive concerns. A one-way ANOVA with post-hoc comparisons using the Tukey test was conducted to compare the mean score of the Swedish RCAC scale of three groups with a certain, uncertain or no wish for (additional) children.