Doctors and nurses often don’t get enough training on how to help teenagers develop healthy eating habits. Researchers tested a new way to teach healthcare providers about teen nutrition using a teaching method called Merrill’s First Principles. They trained 100 healthcare workers—some using the new method and others using traditional training. The group that received the new training learned significantly more and felt more satisfied with their education. This suggests that using better teaching methods could help healthcare providers give teenagers better nutrition guidance, which is important since the eating habits teens develop now often stick with them for life.

The Quick Take

  • What they studied: Whether a specific teaching method (Merrill’s First Principles) helps healthcare providers learn more about nutrition for teenagers compared to regular training methods.
  • Who participated: 100 healthcare providers (doctors, nurses, and other health workers) from a health network in Damghan, Iran. They were divided into two groups: 40 received the new training method and 50 received standard training.
  • Key finding: Healthcare providers who received training using Merrill’s First Principles improved their nutrition knowledge by 42%, compared to only 25% improvement in the group that received standard training. This difference was statistically significant, meaning it’s very unlikely to have happened by chance.
  • What it means for you: If you’re a teenager or parent, this suggests that healthcare providers trained with better teaching methods may be able to give you more accurate and helpful nutrition advice. However, this study only measured whether doctors learned better—it didn’t yet test whether this actually improves teenagers’ eating habits.

The Research Details

This was a quasi-experimental study, which means researchers compared two groups but didn’t randomly assign people to groups (they used convenience sampling instead). One group of 40 healthcare providers received training designed using Merrill’s First Principles—a teaching method that focuses on practical, real-world learning. The other group of 50 providers received standard training. Both groups took a knowledge test before training, right after training, and again two weeks later. They also filled out a satisfaction survey.

Merrill’s First Principles is a teaching approach that emphasizes learning through real problems, building on what people already know, and practicing skills in realistic situations. The researchers believed this approach would work better than traditional lecture-style training for teaching healthcare providers about teen nutrition.

The study measured two main things: how much healthcare providers learned about nutrition (using a 12-question test) and how satisfied they were with their training (using a 10-question survey). They used a statistical method called ANCOVA to compare the groups while accounting for differences in their starting knowledge.

Many healthcare providers don’t receive formal training in adolescent nutrition, even though what teenagers learn about eating habits often affects their health for the rest of their lives. This study is important because it tests whether using a better teaching method can help fix this problem. If Merrill’s First Principles works well for training healthcare providers, it could be used in other health education programs to improve how doctors and nurses teach patients about nutrition.

Strengths: The study had a control group for comparison, measured knowledge at multiple time points (including a follow-up), and used a validated teaching method. The statistical analysis was appropriate for the study design. Weaknesses: The sample size was relatively small (100 providers), participants weren’t randomly assigned to groups (which could introduce bias), and the study only measured provider knowledge—not whether this training actually changed how they treat patients or improved teen health outcomes. The study was conducted in one location in Iran, so results may not apply everywhere.

What the Results Show

Healthcare providers who received training using Merrill’s First Principles showed much greater improvement in nutrition knowledge compared to those who received standard training. The intervention group’s average test score jumped from 7.52 points (out of 12) before training to 10.71 points after training—a 42% increase. In comparison, the control group improved from 7.31 to 9.17 points, which is only a 25% increase.

When researchers adjusted for the fact that both groups started at slightly different knowledge levels, the difference between groups was very statistically significant (p < 0.001). This means there’s less than a 1 in 1,000 chance this difference happened by random luck. The effect size was also large (d = 0.9), meaning the difference was meaningful and substantial, not just a tiny statistical quirk.

Two weeks after training ended, the intervention group maintained their higher knowledge level (8.27 points), which was still significantly better than their starting point. This suggests the learning stuck around, at least in the short term. Healthcare providers who received the new training were also much more satisfied with their education (42.3 out of 50 on the satisfaction scale) compared to those who received standard training (36.8 out of 50).

The satisfaction scores are particularly interesting because they suggest that not only did providers learn more with Merrill’s First Principles, but they also enjoyed the training more. Higher satisfaction might mean providers are more likely to use what they learned and to seek out similar training in the future. The fact that knowledge was maintained at the two-week follow-up suggests the training created lasting learning, though longer follow-up periods would be needed to know if this benefit continues for months or years.

This study adds to existing research showing that Merrill’s First Principles can improve learning in health education. Previous studies have shown this teaching method works well in various healthcare settings, but this appears to be one of the first studies specifically testing it for adolescent nutrition training. The large improvement (42% vs. 25%) is consistent with other research showing that principle-based teaching methods outperform traditional approaches.

The biggest limitation is that this study only measured whether healthcare providers learned more—it didn’t test whether this actually changed how they treat patients or whether teenagers’ eating habits improved. The study was also relatively small and conducted in only one location, so results might be different in other countries or healthcare systems. Because participants weren’t randomly assigned to groups, there’s a possibility that the groups were different in ways that affected the results. Finally, the follow-up period was only two weeks, so we don’t know if the benefits last longer than that.

The Bottom Line

Healthcare organizations should consider using Merrill’s First Principles when designing training programs for providers about adolescent nutrition. The evidence is fairly strong (based on this well-designed study) that this teaching method produces better learning and higher satisfaction than standard training. However, more research is needed to confirm that this improved provider knowledge actually leads to better health outcomes for teenagers.

Healthcare administrators and educators should care about this research because it suggests a better way to train doctors and nurses. Healthcare providers who work with teenagers might benefit from seeking out training based on these principles. Parents and teenagers might eventually benefit if more healthcare providers receive this improved training, though that hasn’t been proven yet.

Based on this study, healthcare providers showed improved knowledge immediately after training and maintained it for at least two weeks. However, we don’t know how long the benefits last beyond that. It’s reasonable to expect that providers would maintain this knowledge for several months, but longer studies would be needed to confirm this.

Want to Apply This Research?

  • If you’re a healthcare provider, track the number of specific nutrition recommendations you give to teenage patients each week (for example, recommendations about calcium intake, hydration, or balanced meals). Compare this before and after receiving training based on Merrill’s First Principles to see if you’re applying your new knowledge.
  • Healthcare providers could use an app to log nutrition topics they discuss with teen patients, set reminders to ask about eating habits during appointments, and track which nutrition topics they feel most confident teaching. This reinforces the training and helps identify areas where additional learning might help.
  • Track provider confidence levels monthly using a simple 1-10 scale for different nutrition topics relevant to adolescents. Also monitor how often providers initiate nutrition conversations with teen patients. Over time, this data shows whether the training’s benefits are maintained and where additional support might be needed.

This research shows that a specific training method helps healthcare providers learn more about adolescent nutrition. However, this study only measured provider knowledge—it did not test whether this training actually improves teenagers’ eating habits or health outcomes. Before making major changes to healthcare training programs, organizations should consider this study alongside other research. If you’re a teenager or parent seeking nutrition advice, consult with your healthcare provider or a registered dietitian. This information is for educational purposes and should not replace professional medical advice.