Setting and sample
Calculation for sample size determination was carried out considering the difference for 2 independent groups utilizing the G*Power software (version 3.1.9.2). In addition, a two-tailed hypothesis, an effect size of 0.50 and an α error probability of 0.05 with a β level of 20% were used. Lastly, a desired power analysis of 80% (1-β error probability) and an allocation ratio (N2/N1) of 1 were used for the sample size calculations. Therefore, a total sample size of 128 participants was calculated with at least 64 participants per group. The sample was recruited through a consecutive sampling method using a successive simple method by the same online survey for both URJC and UCM universities, obtaining up to 140 freshman nursing degree university students. Subjects were enlisted from freshman students from URJC receiving hybrid education and students from UCM receiving virtual education. Both groups were matched according to age (19 years old) and sex (all participants were female nursing freshman university students). Participation selection and inclusion criteria included several parameters: (1) female students of 19 years old; (2) subjects enrolled in the freshman nursing degree class at URJC and UCM, and (3) single subjects without children or dependents who were living with their families. Exclusion criteria comprised male and non-freshman nursing students, aged different from 19 years old, who studied in other universities different from UCM and URJC, native speakers different from Spanish language, and non-single participants with children or dependents.
Ethical consideration
The ethics committee of Universidad Rey Juan Carlos (code: 2,910,202,121,221) approved this research, and all subjects signed the informed consent form before the beginning of the study. Furthermore, the declaration of Helsinki was considered and rules for human experimentation were taken into account.
Procedure
Data collection was carried out using the same online survey which was completed by both groups for approximately 45–60 min in October 2021. This online method for both groups overcame common biases of face-to-face surveys. The feasibility, applicability, and clarity of the research tools were previously stated due to all questionnaires were valid, reliable and transculturally adapted to Spanish language. Permissions to use these tools were not required due to these questionnaires were available without any fee or copyright. Thus, a pilot study was not necessary because the clarity of all items were reported in previous studies. Baseline measurements were self-reported including general questions associated with demographic variables: (1) sex (all students were female), (2) weight, (3) height, (4) body mass index ([BMI] kg/cm2) and (5) all students aged 19 years old.
Freshman students from both universities took the same lectures on campus during the first and second semesters and same weeks of pre-clinical rotation in the second semester according to education schedule requirements of Madrid government, Spain. One group received all lectures as virtual mode using a team platform called “Aula Virtual URJC” [
17] and another one giving lectures by alternating one week using a face-to-face format on campus and the following week using a virtual format with the platform called “Hybrid UCM” [
18] to compare them. Both universities presented similar nursing schools due to they were public institutions from the same rigorous criteria for evaluation according to the Madrid regional government and Spanish National Agency for Quality Assessment and Accreditation. In addition, students from both public universities presented a similar medium socio-economic status due to both nursing schools required similar financial fees and access requirements.
Next, participants completed the following test the same day at both universities at the end of academic year (freshman). Freshman students were new to the university experience. They were students who arrived from high school and who had also experienced virtual teaching and confinement during the acute phase of the pandemic.
Measurements
Rosenberg Self-Esteem Scale (RSE) [
19,
20]. The RSE questionnaire consists of 10 questions, scored from 1 to 4 points, (4 = strongly agree, 3 = agree, 2 = disagree, 1 = strongly disagree). Indeed, 5 statements present positive direction, as well as other 5 statements show negative direction. The authors of the questionnaire set limits for this scale, but a range of scores between 20 and 30 points is usually considered the normal range. If the score was greater than the normal range, such as result would indicate high self-esteem, whereas if the result was less than normal, low self-esteem is indicated. The scale has high reliability with test–retest correlations in the range of 0.82 to 0.88 [
19] and 0.87 for Spanish population [
20].
Ten CD-Risk, Connor-Davidson Risk Resilience Scale (CD-RISC) [
21,
22]: Resilience was evaluated using the short version of 10-items CD-RISC that was validated in Spanish by Notario-Pacheco et al. [
21]. The scale consists of 10 items which corresponded to those numbered 1, 4, 6, 7, 8, 11, 14, 16, 17 and 19 from the original scale designed by Connor and Davidson [
22]. The other numbered items were removed in this short version. Participants self-reported the most suitable response for each question of the Spanish validated scale [
21]. The response format is a five-point Likert-type scale from 0 (totally disagree) to 4 (totally agree).The final score is the sum of all the responses obtained for each item (range from 0 to 40 points), and greater scores show higher resilience level. The reliability of 10-items CD-RISC is defined by a Cronbach’s α of 0.85, and the weights in factor analysis are within the range of 0.48 to 0.76.
Beck Anxiety Inventory (BAI) [
23,
24]. The BAI questionnaire contains a list of 21 symptoms indicating anxiety with a 4-point Likert scale ranging from not at all to severe, and the degree to which each symptom affected them during the last week. Scores for each element were added up, as well as the total score ranged 0–63 points. If total scores ranged 0–7, a minimum anxiety level was considered; if total scores ranged 8–15, mild anxiety level was obtained; if total scores ranged 16–25, moderate anxiety level was obtained, and finally if total scores ranged 26–63, severe anxiety level was established [
23]. Also, in the version adapted for the Spanish population, the instrument showed a high internal consistency with a Cronbach’s α coefficient of 0.92 and a test–retest reliability of 0.75. The BAI has a high internal consistency (Cronbach’s α from 0.90 to 0.94). The correlation between the items and the total score ranged from 0.30 to 0.71. The test–retest reliability after one week ranged from 0.67 to 0.93, and after seven weeks, the reliability was 0.62 [
24].
Beck Depression Inventory (BDI, BDI-II) [
25,
26]. The BDI is questionnaire with a group of 21 items, and all questions use a Likert scale for answers. Indeed, internal consistency showed an α of 0.78. Items of the sample (i.e. sadness) presented responses such as “I don’t feel sad” or “I feel sad most of the time”. Indeed, the original version of the BDI-II manual [
25] considered cut-off values and depression grades such as: (1) minimal depression ranged from 0 to 13 points, (2) mild depression ranged from 14 to 19 points, (3) moderate depression ranged from 20 to 28 points, and (4) severe depression ranged from 29 to 63 points. The Spanish adaptation of Sanz and Vázquez [
26] assumes the cut-off scores designed by Beck et al. [
25], and the reliability of the instrument is high both in terms of internal consistency (Cronbach’s α coefficient = 0.83) and temporal stability (test–retest correlations ranged between 0.60 and 0.72 for 3 different subgroups regarding the total sample).
Academic Stress Coping Scale (ASCS) [
27]. The ASCS scale is a subscale of the Academic Stress Questionnaire (CEA) questionnaire, an instrument made up of three scales, which is used to assess academic stressors, stress responses, and stress coping strategies. The ASCS scale is made up of 23 items, formulated to evaluate the cognitive and behavioral strategies used by the student when facing situations of academic stress. It is a scale with Likert-type responses to each item for which the student can choose between five options: Never (1), Sometimes (2), Quite a few times (3), Many times (4), and Always (5). The reliability of the ASCS scale has a general Cronbach’s coefficient for this study of 0.885. In turn, this coping scale is divided into three factors that are specified below: (1) Factor 1 (1 COP). Positive Reassessment: This dimension groups nine items (1, 3, 4, 5, 6, 14, 17, 18, and 19) that present different ways of coping aimed at creating a new positive meaning about the problem or academic difficulty. This factor underlines its active and positive character in propositions of direct quotes such as “When I face a problematic situation the night before the exam, I try to think that I am prepared to do it well” or “When I face a complicated situation, in general, I try not to give it importance to the problems” [
27]. Its internal consistency according to Cronbach’s α was 0.668; (2) Factor 2 (COP 2). Search for Social Support includes seven items (2, 8, 10, 13, 20, 21, and 23) to assess active and behavioural coping based on the student’s search for information and advice as social support for the problem and also for understanding by other people as emotional support for what they are experiencing. Its internal consistency according to Cronbach’s α was 0.727; and (3) Factor 3 (COP 3). Planning and management of personal resources includes seven items (7, 9, 11, 12, 15, 16, and 22) that refer to the activation of strategies based on analysis and reason to change the problematic situation and that denotes a type of behavioural and active coping. Its internal consistency according to Cronbach’s α was 0.741 for this study.
Data Analysis
Regarding quantitative data, all variables were examined for normality of distribution using the Kolmogorov–Smirnov test, and data were considered normally distributed if P > 0.05. Descriptive analyses, including calculation of means, standard deviations (SD), and 95% confidence intervals (CI) were calculated for quantitative variables according to normal distributions. Median and 95% CIs were described for non-normally distributed data. For categorical data, frequencies as well as % were used to describe these values. Differences between groups were contrasted using independent Student’s t considering the Levene´s test for equality of variances or Mann–Whitney U tests when variables showed normal or non-normal distribution. Differences between groups were compare using the chi-square test for qualitative variables. In addition, linear regression analyses were performed to predict the Beck Depression Inventory (BDI, BDI-II) levels as the outcome measurement that showed statistically significant differences between both groups. These linear regression analyses were performed using the R2 coefficient to quantify the adjustment quality according to the pre-established values for F probability (Pin = 0.05, Pout = 0.10). Descriptive data which showed statistical differences between both groups (height and weight) were considered independent variables. Depression levels (BDI, BDI-II) were considered the dependent variable. In all analyses, statistical significance was established with a P-value < 0.05 with a 95% CI. Lastly, each analysis was carried out with the statistical software SPSS (using the version 19.0; from Chicago, IL, USA).