Spaced repetition and other key factors influencing medical school entrance exam success: insights from a French survey

Background

First-year medical candidates encounter steep learning demands when transitioning from high school to university. Spaced repetition– a method of distributing review sessions over time– improves long-term memory retention. This study assessed its effectiveness alongside lifestyle and academic factors in students preparing for the medical school entrance examination.

Methods

In 2023, all 618 candidates at the University of Rouen were invited to complete a post-exam, self-administered questionnaire; 523 responded (84.6%). We collected data on revision methods (e.g., spaced repetition, reviewing archives of previous exams), participation in private preparatory classes and summer courses, lifestyle behaviors (e.g., sleep duration, physical activity or smoking), and secondary-school grades. Predictors of success were identified through univariate analyses. A multivariate logistic regression was then conducted to determine independent predictors of success.

Results

Of 523 respondents, 134 (25.6%) passed the entrance exam. In univariate analysis, successful candidates significantly more often used spaced repetition (44.8% vs. 20.3%; p < 0.001), reviewed archives of previous exams, attended private preparatory classes or summer courses, and had higher secondary-school grades. In multivariate logistic regression, independent predictors of success included spaced repetition (aOR 2.09; 95% CI, 1.16–3.48), secondary-school grades (aOR 3.19; 95% CI, 2.33–4.37), private preparatory class attendance (aOR 2.02; 95% CI, 1.11–3.66), sleep duration (aOR 1.49; 95% CI, 1.12–1.99), and regular sport practice (aOR 1.81; 95% CI, 1.13–2.93).

Conclusions

Admission success in the medical school entrance examination appeared to be influenced by multiple factors: while spaced repetition significantly enhanced performance, academic background, private preparatory classes, and healthy lifestyle habits also contributed. These findings support integrating validated study techniques and wellness strategies into university support programs for entrance examinations.

Practice points

• Students frequently feel underprepared for the transition from small-group secondary-school instruction to large-lecture university formats.

• Structured study strategies– such as spaced repetition– are associated with higher success rates in medical school entrance examinations.

• Additional factors– including sleep duration, regular physical activity, attendance at private preparatory classes, and strong secondary school performance– also correlate with admission success.

Background

Medical school (MS) entrance examinations vary considerably across regions of the world. In many countries, these highly selective assessments expose students to learning difficulties and increased anxiety. This vulnerability stems from the abrupt transition from secondary to higher education [1–4]. Students move from small-group, instructor-led instruction in high school to large-scale lectures in university auditoriums, underscoring the need for autonomous learning: they must organize course materials, integrate information from diverse sources, and manage their own study schedules. Following a 2019 French reform, candidates have only one attempt at the MS entrance examination in the year following their secondary school diploma, although alternative pathways permit later entry [5]. First-year curricula cover, despite variations across institutions, foundational disciplines such as human anatomy, cellular biology, physics, and the social and human sciences. End-of-semester assessments, conducted in two sessions, have evolved from traditional multiple-choice tests to multimodal formats (diagram annotation, cloze-text exercises, and open-ended questions) to more accurately evaluate students’ knowledge and clinical reasoning skills. Factors contributing to success in MS entrance examinations —and, more broadly, to improved learning outcomes—remain poorly understood [4–7]. Fortunately, the low tuition fees at French public universities help to alleviate the financial burden on students.

Students often practice massed learning to build up a strong initial memory that gradually fades without further revision. Massed learning consists in learning a large amount of information over a short period [8]. In contrast, spaced repetition is a recognized method for improving memory retention and long-term recall of information. The spaced repetition method involves strategically spreading out learning repetitions over time. This method appears to enhance learning and slow down the natural decline of memory, thus enabling prolonged retention [9–11]. A schematic illustration of spaced repetition learning is presented in Fig. 1.

Fig. 1.

Evolution of memory retention over time with spaced repetition. The pink curve shows the evolution of memory retention with expanded spaced repetition, while the grey curve shows that with mass learning. R = Review

First-year medical students are tasked with mastering a large volume of foundational knowledge primarily through memorization, as their early training is preclinical and affords little engagement with complex clinical practice [12]. To meet this challenge, students often employ various learning strategies, including massed learning, spaced repetition, and active recall, each with distinct advantages and limitations [9, 13, 14]. Massed practice, involving intensive study in a short period, can yield quick short-term gains but is associated with rapid forgetting, whereas spaced repetition (distributed practice), which spreads learning sessions over time seems to produce significantly better long-term retention [15]. Active recall (retrieval practice via self-testing) engages students in actively retrieving information from memory; this technique strengthens memory consolidation and has been shown to boost learning and performance across a range of tasks [15]. However, it also demands more cognitive effort and discipline than passive review. While mastering these cognitive strategies is crucial, success may also be influenced by factors beyond study methods alone. For instance, regular physical exercise has been linked to enhanced cognitive function and memory, potentially benefiting academic performance, whereas habits like tobacco use have been associated with cognitive impairments that could hinder learning [16, 17]. The purpose of this study was to examine the factors influencing success in MS entrance examinations focusing on the learning strategy.

Methods

Design and setting

A retrospective, single-center, cohort study was conducted, based on the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines [18]. All students preparing for the MS entrance examinations in the year 2022–2023 at the University of Rouen (France) were invited to participate in an individual anonymous self-questionnaire (Table 1). No student had prepared for this examination the previous year. Given that the examinations in Rouen University were conducted using digital tablets (Apple iPad [Apple Inc, Cupertino, CA]). At the end of the end-of-year examination, students received study information and were invited to complete the questionnaire voluntarily. During the 2022–2023 academic year, admission to medical school followed a numerus apertus model. A portion of available seats was allocated to the highest-ranking candidates who met a minimum academic standard, regardless of a predefined score threshold, while the remaining seats were filled strictly based on entrance exam ranking. Selection was based on performance in 14 core scientific subjects. Success was defined as the number of those admitted students who progressed into second-year medical studies.

Table 1.

Survey in which students were invited to participate during end-of-year examinations

Questions	Answers
Learning technique
1) Did you predominantly employ the spaced repetition method as your primary learning strategy throughout this year, i.e., utilizing it for over 75% of your study time? (As a reminder, spaced repetition entails initially learning the material on the day of instruction and subsequently revisiting it at progressively extended intervals, as part of planned review sessions.)	Yes / No
2) What was your daily average learning time?	_ hours
3) Have you trained by reviewing the archives of previous exams?	Yes / No
4) Have you enrolled in a private preparatory school for support this year?	Yes / No
5) Have you undertaken any private summer courses to prepare for this year?	Yes / No
Health and Lifestyle
1) What was your average nightly sleep duration?	_ hours
2) Did you primarily reside alone during this year?	Yes / No
3) Did you have a long commute to university, defined as more than an hour?	Yes / No
4) Do you smoke?	Yes / No
5) Did you practice sports once a week or more?	Yes / No
6) Did you embark on this year alone, devoid of companionship or a romantic partner?	Yes / No
Secondary school
1) What were your average secondary school marks (rounded to the nearest whole number)?

Statistical analysis

Continuous data are presented as mean ± SDs (standard deviations) or median (IQR; interquartile range). Categorical variables are presented as count (percentages). Statistical comparisons were performed by a Welch’s t-test for normally distributed data, the Mann-Whitney U test for data with a skewed distribution, and the Chi-Square and Fisher’s exact tests for categorical data. To assess the factors for end-of-year examinations success, a univariate analysis was performed using data on learning technique and lifestyle. Multivariate analysis was performed to define independent predictive variables using logistic regression. All collected variables were included in the multivariate logistic regression model. A p value < 0.05 was statistically significant.

A predetermined threshold of 20% for missing data was established in advance. Variables with more than 20% missing data were excluded from the model. Fortunately, none of the variables exceeded this threshold. For variables with less than 20% missing data, we applied a multiple imputation by chained equations (MICE) procedure.

The data were analyzed using Statistical Package for Social Sciences (SPSS, version 28.0.1.1; IBM, Armonk) and R statistical software (version 3.5.2; R Foundation for Statistical Computing, Vienna, Austria).

Results

Descriptive and univariate analysis

A total of 523 responses were gathered over 618 students (84.6%) administratively registered at the beginning of the academic year, with 134 respondents (25.6%) achieving success in the MSA examinations, while 389 (74.4%) did not. Spaced repetition was used by 139 students (26.6%). Table 2 provides a summary of the descriptive and univariate analysis of categorical variables. Although individual ages were not collected to preserve the anonymity of outlier respondents, all participants were recent secondary school graduates and were therefore estimated to be between 16 and 20 years of age.

Table 2.

Univariate analysis of categorical variables comparing students who succeeded in the end-of-year examinations with those who did not

	Total n = 523	Failure n = 389	Success n = 134	P value
Spaced Repetition	139 (26.6%)	79 (20.3%)	60 (44.8%)	< 0.001
Archives of Previous Exams	454 (88.2%)	326 (85.3%)	128 (96.2%)	< 0.001
Private Preparatory Class	351 (67.5%)	239 (61.9%)	112 (83.6%)	< 0.001
Private Summer Courses	391 (75.5%)	275 (71.4%)	116 (87.2%)	< 0.001
Living Alone	216 (41.6%)	155 (40.2%)	61 (45.9%)	< 0.25
Long Daily Commute	114 (22.1%)	96 (24.9%)	18 (13.6%)	< 0.01
Smoking	36 (7.1%)	31 (8.2%)	5 (3.8%)	< 0.093
Sports Practice	255 (49.2%)	178 (46.2%)	77 (57.9%)	0.02
Social Isolation	156 (31.3%)	114 (30.8%)	42 (32.6%)	0.71

In the cohort, the median daily learning time was 8 h (IQR, 6–9), with the median learning time being statistically higher in the group that succeeded in the MSA examinations [9 h (IQR, 7–10), versus 8 h (IQR, 6–9)]. The average daily sleep duration was 7 h (IQR, 6–7), and this sleep duration was significantly higher in the successful group [7 h (IQR, 6–7), versus 6 h (IQR, 6–7)]. The median secondary school mark was 14 (IQR 14–16). Successful students achieved significantly higher marks [16 (IQR, 14–16), versus 14 (IQR, 12–14)].

Multivariate analysis

In logistic regression, a statistically significant relationship was found between success and spaced repetition (adjusted Odds Ratio = 2.09; 95%CI = 1.26–3.48; P = 0.01). Additionally, success was significantly associated with attending private preparatory classes, secondary school marks, sleep duration, and sports practice. Relationships are presented in Fig. 2, depicting the Forest Plot for all the variables under study.

Fig. 2.

Forest plot displaying the relationships between success and variables studied

Discussion

In this study, spaced repetition was associated with higher admission rate in the MS entrance examinations alongside sleep duration, physical activity, attendance at private preparatory class and secondary school grades. The adjusted odds ratio indicates that students who used spaced repetition were approximately twice as likely to succeed in the entrance exam (OR 2.09; 95% CI, 1.26–3.48; p = 0.01), highlighting the potential relevance of this method in academic preparation.

These results are consistent with the benefits of the spacing effect which mitigates memory decay and enhances long-term consolidation [19–23]. Yet the mechanisms underlying the consolidation of long-term memory remain a topic of ongoing research, with multiple hypotheses coexisting. For instance, the deficient processing hypothesis suggests that massed learning leads to a reduction in voluntary attention and incomplete integration of the information [22, 24, 25]. Also, the study phase retrieval hypothesis postulates that spaced repetition strengthens the initial memory trace of information [22, 26, 27]. Retrieval appears to be enhanced when information is associated with a range of contextual elements during each repetition. It was also observed that introducing greater diversity in context —such as different times, people, places, or sensory inputs— enhances retrieval, a phenomenon known as the context variability hypothesis [28]. Memory consolidation seems to rely on an initial pathway for information encoding, subsequently reinforced through repetitive stimulation facilitated by synaptic plasticity and contextual diversity [22]. This observation has driven the evolution of multimodal pedagogic approaches with incorporation of supervised practical lessons and multimedia supports in the teachings. Therefore, this survey did not capture specific spacing schedules, but prior research indicates that expanding-interval schedules (e.g., 2–7–17–40 days) yield better retention than contracting or fixed intervals, and that any form of spaced repetition outperforms massed learning [29].

Beyond revision strategies, multivariate analysis revealed that higher secondary school grades and participation in private preparatory classes independently predicted success in the MS entrance examinations, consistent with the exam’s function as a filter for top academic performers. This suggests these students may adapt more readily to changes in curricular content and instructional formats. Notably, Schneid et al. reported that second-year medical students retained, on average, only 60% of first-year basic science knowledge, and other studies have documented individual retention rates ranging from 37 to 81% several months after examinations [30, 31].

Most students (67.5%) attended private preparatory classes (PPC), which comprise small study groups throughout the academic year. PPC providers offer paid work-packages and operate independently from the university, yet their regular assessments supplement university courses and reinforce active retrieval practice. However, participation in PPC may reflect selection bias, as enrollees could possess greater motivation, resources, or adaptability—raising concerns about equitable access and socio-economic disparities.

The analysis also revealed that two independent lifestyle factors were significantly associated with success in the medical school entrance examination: each additional hour of sleep per night increased the odds of success by 49% (OR 1.49; 95% CI, 1.12–1.99), and students who reported engaging in regular physical activity (at least once per week) had 81% higher odds of success compared to those who did not (OR 1.81; 95% CI, 1.13–2.93). Consistently with our results, Mazza et al. reported that sleeping between repetition-improved the quality of memory consolidation in foreign word lists. In their experiment, students with sleep between repetition learning showed better results than no sleep students at 1 week and 6 months retrieval tests [8]. These results tended to confirm the active consolidation of memory during sleep involving several modifications in the knowledge network [32–34].

Regarding physical activity, Trott et al. noted that physically active students were more likely to achieve high academic performance in a meta-analysis of 36 studies, mirroring our findings. Likewise, a study of 409 medical students reported that those who exercised regularly were three times more likely to earn a high GPA [35, 36].

Social isolation surprisingly was not linked with success nor failure. This finding appears to be contradictory with the expected benefits of contextual enhancement trough repetitions.

Finally, it is crucial to recognize the limitations of our study. Although we achieved a high response rate, there is a notable reporting bias. Due to the use of a non-standardized questionnaire, students might not have fully grasped the question regarding their use of spaced repetition. Future studies could mitigate recall bias by collecting data prospectively during the academic year or by using validated instruments to assess learning strategies. Furthermore, we did not request students to specify their study schedules, which orientated the questionnaire in favor of organized methods over massed learning or disorganized approaches. However, 73% of students still indicated not using a pre-established study schedule. Future research should explore the long-term impact of spaced repetition on medical students’ academic performance beyond entrance examinations, and assess the relative effectiveness of different scheduling strategies, such as expanding versus fixed intervals. Moreover, we performed a retrospective study and other confounding factors beyond the scope of multivariate analysis may have been overlooked. Although the response rate was high, we cannot completely rule out non-response bias; however, the timing, anonymity, and broad participation likely limited this risk. Finally, we did not explore statistical interactions between explanatory variables, as subgroup stratification would have led to small sample sizes and reduced the reliability of estimates. Such analyses could be more appropriately addressed in future studies with larger samples or a dedicated design.

Conclusions

Our results indicate that spaced repetition, sleep duration, physical activity, preparatory course attendance, and secondary school grades were associated with higher admission rates. These findings suggest that success in the MS entrance examination may be multifactorial. Future research using more granular assessments of study strategies and a broader set of potential predictors is needed to delineate the relative impact of these factors and to inform the development of targeted guidance from universities and faculty for student preparation.

Abbreviations

MS

Medical school

STROBE

Strengthening the reporting of observational studies in epidemiology

SD

Standard deviation

IQR

Interquartile range

MICE

Multiple imputation by chained equations

PPC

Private preparatory classes

Author contributions

Conception and design of the work: J.B., C.M., J.L., O.T. Acquisition, analysis: J.B., C.M., O.T., M.D., J.L. Interpretation of data: J.B., C.M., O.T., M.D., J.L. Drafting or substantive revision: J.B., C.M., O.T., M.D., J.L., S.D., F.C., F.E., N.R.

Funding

This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

Data availability

All data are available from the corresponding author upon reasonable request.

Declarations

Ethical approval and consent to participate

The research protocol (E2024-78) was reviewed by the local Ethics Committee. This Ethics Committee, named “Comité d’Éthique pour la Recherche sur Données Existantes et/ou hors loi Jardé - CHU de Rouen” waived the requirement for consent to participate. The committee confirmed that the protocol raises no ethical concerns and complies with French research regulations.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.