Predictors of first-time national board passage for respiratory therapy associate degree program graduates

Current knowledge

All healthcare programs, not just respiratory therapy, have graduates who fail to pass their national licensing exams and thus cannot obtain their license. As a result, many previous studies have examined the first-time pass rates of various health profession national board exams, seeking to understand any correlations between passage rates and various academic and nonacademic variables. Yet, no previous respiratory care research had examined a comprehensive list of such variables as potential predictors of success on the national board exams enacted in 2015 (and in place until 2027).

What this paper contributes to our knowledge

A logistic regression model using data from 254 graduates of associate degree respiratory care programs revealed that four of the 26 independent variables were significant predictors of passing the TMC on the first attempt. These significant variables are grades in four courses: Pre-Program Biology A&P, Pharmacology, Cardiovascular Physiology, and Pediatric/Neonatal Critical Care.

Introduction

The respiratory therapy workforce has faced persistent shortages for more than a decade, driven by an aging workforce, burnout, clinical practice site capacity limitations, and a shortage of qualified faculty. ¹ To practice, respiratory therapists must pass national board exams administered by the National Board for Respiratory Care (NBRC). In 2015, the NBRC restructured these exams into two parts: the Therapist Multiple Choice (TMC) exam and the Clinical Simulation Exam (CSE). Candidates who achieve a high-cut score on the TMC become eligible for the CSE and, upon passing it and any additional state requirements, earn the Registered Respiratory Therapist (RRT) credential. Those who achieve only a low-cut score may practice as a Certified Respiratory Therapist; however, securing a respiratory therapy position is more difficult without the RRT credential. ²

Since the introduction of the new TMC in 2015, the first-time passage rates have decreased. In 2014, the overall pass rate was 79.8%; by 2024, only 79.5% of candidates achieved the low-cut score, and 69.9% achieved the high-cut score on their first attempt. ³ This decline delays workforce entry and contributes to ongoing staffing shortages. ⁴ Inadequate passage rates also affect the accreditation of respiratory therapy programs. The Commission on Accreditation of Respiratory Care (CoARC) accredits respiratory therapy programs and requires that 80% of new candidates pass their national board exams on the first attempt.

To better support students and programs, respiratory therapy educators need evidence-based indicators to predict performance on the TMC. Yet, prior to this study, only five studies examined respiratory therapy programs and prediction of success on national board exams,^4–8 with two others focused on program completion.^9,10 All but one ⁵ was conducted before the national board exams adopted in 2015, and only two^5,11 focused on students in associate degree programs, despite the vast majority of respiratory care students in the United States being educated via associate degree programs. ¹² Most had small sample sizes (e.g., less than 80 students) and examined only a few predictor variables. Indeed, the only previous study that included a large number of graduates (n = 394) ⁷ was focused on a baccalaureate respiratory program, and was conducted in 2008, well before the current national board exams were implemented. Overall, this literature review therefore revealed the need for a study focused on the current national board exams for a larger cohort of associate degree respiratory therapy program graduates that also examined a broader range of predictor variables.

Methods

This non-experimental quantitative study involved a post hoc secondary analysis of existing data extracted from a national dataset and from systems within two participating Midwestern community colleges. Because the study relied on retrospective, pre-existing records, the design inherently limited control over data completeness, variable selection, and potential confounding factors. The goal was to determine whether a statistically significant relationship existed between the dependent variable (TMC first-time passage) and 26 independent variables. Logistic regression analysis was used to identify variables most predictive of first-time TMC success.

The convenience sample consisted of students who graduated from an associate degree respiratory therapy program at two community colleges in one Midwestern state, during one of six academic years (2015-2020). These respiratory therapy programs are both 28-month CoARC-accredited programs, and their graduates must pass the TMC to obtain a license and practice as an RRT. The sample was limited to students who had begun the respiratory therapy program at the college and had not transferred from another program. Student records with missing data were excluded, leaving complete records for 254 students. Because this research used existing databases, staff associated with a university’s Human Subjects Institutional Review Board determined no IRB approval was needed.

Secondary data were obtained from two sources. The first involved public statistics published by the NBRC on the TMC scores. The second was compiled using existing data from students’ application for admission to the respiratory therapy professional program, prerequisite course grades, core curriculum course grades, clinical hours and grades, board exam preparation type, and student demographics.

The dependent variable was TMC first-time passage using the high-cut score, and this was coded as 0 = No/1 = Yes. There were 26 independent variables including the final grades for 22 courses: three required pre-program science courses (Pre-Program Biology Anatomy and Physiology (A&P), Microbiology, and Chemistry); 13 core professional curriculum classes (Respiratory Therapy (RT) Physics, Respiratory Patient Care Skills, RT Equipment and Procedures, Introduction to Respiratory, Pharmacology, RT Physiology, Introduction to Mechanical Ventilation, Pulmonary Physiology, Adult Mechanical Ventilation, Cardiovascular and Renal Physiology, Pediatric/Neonatal Critical Care Pulmonary Diagnostics and Rehabilitation, and Health Care Environment); and six core professional clinical courses (RT Clinical I, RT Clinical II, RT Clinical IV, RT Clinical V, RT Advanced Clinical Practicum I, and RT Clinical Rotation VII). Grades in each of these 22 courses were coded as interval data (A = 4.00; A− = 3.70; B+ = 3.30; B = 3.00; B− = 2.70; C+ = 2.30; C = 2.00).

Four additional independent variables included student age (a continuous variable coded as 18 to 60 years); student identified gender (a dichotomous variable coded as 0 = Male/1 = Female); total clinical hours (a continuous variable coded 0 to 800); and board preparatory program type (a dichotomous variable coded as 0 = Lindsey Jones, 1 = Kettering Board Review).

Logistic regression analysis was used to predict students’ performance on the TMC, by building models composed of demographic data and academic variables. Dummy codes were created for each program to remove identifiable markers and for categorical variables to be used in regression analysis. Hierarchical linear modeling (HLM) was explored as an analysis approach and determined not to be a good fit, as the study did not have enough level 2 schools or variables to utilize HLM.

In the initial analysis, the traditional logistic regression procedure was performed to predict the log-likelihood for explaining the outcome. The initial full model with all main effects resulted in no identified significant relationship between the explanatory variables and passing or failing the TMC. Because the findings showed no significance, the model may have been overfitted, which can occur when a model analyzes random error instead of the underlying relationship between the explanatory variables and the outcomes. ¹³ As a result, the model may have required more data than available, and a model selection command was appropriate for further data analysis to adjust for over-fitting.

The stepwise procedure was then used to analyze the data, using the default method involving Fisher’s scoring, which is an iterative method of estimating regression parameters that yield estimates of regression coefficients in terms of standard error. The default order of levels was maintained to model the probability of those failing (model pf = 0) in relation to the explanatory variables. Akaike Information Criterion, Schwarz Criterion, and maximum log-likelihood measurements were calculated to evaluate model fit, and the likelihood ratio test revealed that the model was a good fit (P = <.001). Without such analysis, the inference may have been misleading by containing serious errors not detectable through model fitting procedures. ¹⁴ Results are summarized in the next section.

Results

Four significant predictors were found, all grades in courses: Pre-Program Biology A&P (P = .01), Pharmacology (P = .03), Cardiovascular Physiology (P = .02), and Pediatric/Neonatal Critical Care (P = .01). These four variables predicted TMC outcomes (first-time pass or fail) with 91.9% accuracy.

Logistic regression also generates an odds ratio to determine the predictive power of each independent explanatory variable, while controlling for the other predictors in the model. ¹⁵ For each one unit of increase in course grades, the odds of passing the TMC on the first attempt increased by factors of 8.42 (Pre-Program Biology A&P), 7.20 (Cardiovascular Physiology), 6.65 (Pediatric/Neonatal Critical Care), and 3.55 (Pharmacology). These odds ratios indicate that even modest improvements in final course grades substantially increase a student’s likelihood of first-time TMC passage, underscoring the strong predictive value of performance in these courses.

Although other variables were not deemed significant predictors, several warranted analyses, including gender and age. More than three-quarters of the sample identified as female (n = 203, or 79.9%) and 20.1% (n = 51) as male. While identified gender was not predictive of first-time pass rates, results revealed 74.51% of males passed on the first attempt, while 67.8% of females did so. Student ages ranged from 19 to 56 years (mean = 25.5 years) upon enrollment in the respiratory care program. The majority were between the ages of 18-24, 64% (n = 163), and of such students, 67% (n = 118) were successful on their first attempt of the TMC, although age was not found to be a significant predictor of first-time passage.

Regarding students’ TMC board preparation program type, data revealed that of the 176 respiratory graduates who passed the TMC on the first attempt, 42 participated in Kettering board review (56.8% of all who had that type of preparatory course), and 134 participated in Lindsey Jones (74.4% of all who had that type of preparatory course). This indicates a larger percentage of students who took the Lindsey Jones preparatory course passed on the first attempt, suggesting it may be a more effective preparatory option. Yet, the regression did not find the type of preparation course was a significant predictor.

Another variable examined was the number of clinical hours in which each student participated, with each respiratory therapy program dictating how many clinical hours students must spend in clinical settings. According to CoARC standards, the degree-granting college must ensure time spent in clinical is sufficient for students to acquire all required competencies. Within this study, one program required 850 clinical hours, while the other required 615 clinical hours. Of those who had completed 615 clinical hours, 56.8% (42 students) passed on the first attempt, compared to 74.4% (134 students) of those who had completed 850 clinical hours. Such data could suggest that more clinical hours may improve outcomes; yet, the number of clinical hours was not a significant predictor.

While the regression revealed only four of the 22 courses examined were significant predictors of first-time passage, reviewing the data for each course has value. Descriptive statistics were run for all 22 courses, depicting the number passing the TMC on the first time as broken down by the final grade received in the course. Given space limitations in this article, these data are not presented here but can be found in the complete study report. ¹⁴ Instead, Figure 1 summarizes the percentage of students who received a grade of A in a given course and passed the TMC on the first attempt. The figure lists the courses from highest to lowest first-time passage percentage and highlights the four courses that had demonstrated significance in the stepwise logistic regression. Such visualization is helpful for practitioners to see for each program course, the percentage of students who passed the TMC national board the first time and who had received an A in that given class.OPEN IN VIEWER

Discussion

Healthcare educators continue to strive for 100% pass rates on national board exams; as such, community college respiratory academic communities stand to benefit from these research results. First-time TMC pass rates are considered by many to be the gold standard of respiratory therapy program quality and success, and poor first-time pass rates can pose a threat to accreditation, funding, and overall enrollment. Faculty must therefore understand the implications of performance in the significant courses that identify students at risk of failure on the TMC.

Of the three core program courses deemed significant predictors, two (Cardiovascular Physiology and Pediatric/Neonatal Critical Care) are offered later in the associate degree program, following successful completion of the Pharmacology course. This is important knowledge because the overall respiratory program curriculum is designed to build from simple to more complex concepts as the student progresses. The content presented in each course builds on prior knowledge that is expanded in each subsequent course. By the time they take the Cardiovascular Physiology and the Pediatric/Neonatal Critical Care courses, students have been exposed to more challenging respiratory concepts and are expected to engage in critical thinking application and constructive learning activities. Additionally, these courses emphasize critical thinking, patient assessment, and clinical decision-making, all vital to respiratory care. They teach students how to evaluate patient symptoms and make effective, timely decisions, which are core competencies for an entry-level practitioner. Overall strong success in these specific courses indicates a student has the foundational knowledge, critical thinking, and cognitive skills needed to master and apply respiratory concepts and perform successfully on the TMC.

Students’ performance in these classes can therefore be used to identify students who may be at risk of not completing the program or ultimately failing the licensing exams. Early intervention within those courses could help students become more successful academically and professionally by passing the TMC on the first attempt. This notion is supported by various studies of interventions in nursing programs, including identification of students at risk of failing national board exams.^15,16 Programs can operationalize early remediation by embedding structured checkpoints within these four courses, such as early low-stakes quizzes, midterm progress reviews, or faculty-initiated meetings, to identify students before deficits become entrenched. Programs could also implement targeted tutoring, supplemental instruction, peer-assisted learning, or faculty-led review modules aligned with high-yield content emphasized in these courses. Establishing clear remediation triggers can ensure that support is timely, consistent, and proactive rather than punitive.

Indeed, being able to accurately predict pass or fail outcomes at 91.9% based on grades in four courses supports the recommendation that respiratory educators identify students in need of remediation in these predictive courses. Students with lower grades in Pre-Program Biology A&P, Pharmacology, Cardiovascular Physiology, and/or Pediatric/Neonatal Critical Care courses should participate in formal, rigorous remedial activities to avoid TMC failure. This is an actionable recommendation since three of these courses are taken during the program, and immediate interventions can occur, both within a given class, and once final grades in such courses are known. Embedding remediation within the course sequence also allows faculty to intervene while students are still actively building foundational knowledge, rather than waiting until the end of the program when fewer corrective opportunities remain.

Given the professional standards and requirements connected with the respiratory therapy profession, these results are instructive for other associate degree programs in respiratory therapy (beyond those attending the two colleges involved in this study). Determining four courses predictive of successful pass rates is exceptionally significant to respiratory educators and leaders, and such knowledge can lead to the modifications of admission policies, remediations and mentoring, and curriculum development in respiratory degree programs. These findings also have implications for selective admission filters. The fact that three of the four predictive courses occur after admission suggests that retention-focused strategies may be more impactful than placing greater weight on pre-program science grades. Over-reliance on selective admission criteria risks excluding capable applicants who could succeed with appropriate academic support. In contrast, prioritizing course-embedded remediation, structured mentoring, and academic scaffolding allows programs to support a broader range of students while still improving credentialing outcomes. This approach aligns with the mission of community colleges to expand access while ensuring graduates are well-prepared for professional practice.

Importantly, these findings add to the literature; no previous research examined a comprehensive set of 26 academic and nonacademic potential predictor variables within associate degree respiratory therapy programs focused on the current national board exams. The methods used can serve as a foundation for future research related to predictors of national board exam passage by respiratory therapy graduates, especially with new national board exams slated to begin in 2027.

Research from other healthcare professions, primarily nursing, has also found that pre-program biology and other science courses, as well as some core program courses, are predictive in healthcare national board success.^17,18 Of the limited research on respiratory therapy programs, Ari et al also found a positive correlation between a pre-program science grade and success on the older national board exams. ⁷ No other previous study focused on respiratory therapy looked at core program courses, as was done in this study.

It is important to note that retrospective studies have multiple limitations. First, this study used the stepwise iterative logistic regression process to determine significance in the explanatory variables for model selection, and the overall classification results for pass or fail outcomes should be interpreted with caution; the correct logistic regression model does not always yield reasonable classifications for both groups. Ideally, a study with a goal of classification accuracy should fit the model on one group and then apply the model to another group for cross-validation to determine the generalizability of accuracy across samples. ¹⁴ Also, the iterative process in the stepwise procedure completed multiple tests of the individual coefficients, which dramatically increased the Type 1 error rate for the overall study, thus supporting the need for cross-validation. The cross-validation absence in the present study highlights an important opportunity for future multi-institutional research, where larger, more diverse datasets would allow the predictive model to be tested on independent samples and evaluated for stability and generalizability across programs.

A retrospective study also has no control over the classroom environment to ensure consistency across multiple graduating classes or classroom grading used by different instructors. Additionally, remedial activities and individual motivation factors are extraneous variables not controlled in this study, and a convenience sample from two Midwest community colleges was used. Thus, the generalizability of this study’s findings beyond these two Midwest community colleges should be used with caution until cross-validation can be obtained. Variability in instructional delivery, such as differences in teaching styles, assessment methods, course sequencing, and grading practices, is a common challenge in retrospective educational research and may introduce uncontrolled variation in the data set. Recognizing these limitations underscores the value of future studies that incorporate standardized instructional elements or prospective data collection to better isolate the relationship between course performance and TMC outcomes.

Conclusions

Prior to this study, no research was found that examined 26 academic and nonacademic independent variables for a large number of associate degree respiratory therapy program graduates (n = 254). Stepwise logistic regression analysis revealed a significant positive relationship between grades in four courses (Pre-Program Biology A&P (P = .01), Pharmacology (P = .03), Cardiovascular Physiology (P = .02), and Pediatric/Neonatal Critical Care (P = .01)), and the overall ability to predict TMC outcomes at P = .05. These variables correctly classified the first-attempt pass or fail outcomes on the TMC with 91.9% accuracy. This means that students with higher grades in these four courses are more likely to pass the TMC on their first attempt.

Despite several limitations inherent in retrospective studies (as detailed in the Discussion section), these findings support recommendations that respiratory therapy educators implement remediation activities within and following these specific courses. Such activities may lead to improved first-time national board passage rates, an important goal for both respiratory therapy students and programs.