NCT Research Methods & Evidence-Based Practice 3 — Questions and Answers
Question 1: A fleet technician notes that fuel efficiency has dropped 15% over six months across 40 vehicles. To investigate the root cause, the FIRST step in an evidence-based approach is to:
- Immediately replace fuel injectors on all vehicles
- Define the problem clearly and gather relevant historical data (Correct answer)
- Survey drivers about their habits
- Order a new brand of fuel additive
Correct answer: Define the problem clearly and gather relevant historical data
Evidence-based problem-solving begins with clearly defining the problem and systematically collecting relevant data before implementing solutions.
Question 2: In fleet research, a 'confounding variable' is best described as:
- A variable that directly causes the outcome being studied
- An extraneous variable that influences both the independent and dependent variables (Correct answer)
- A variable with no measurable impact on fleet performance
- The primary metric tracked in a fleet KPI dashboard
Correct answer: An extraneous variable that influences both the independent and dependent variables
A confounding variable is an outside factor that correlates with both the cause and effect, potentially distorting study conclusions.
Question 3: Which type of chart is most effective for displaying the distribution of vehicle repair costs across different cost ranges?
- Pie chart
- Line graph
- Histogram (Correct answer)
- Scatter plot
Correct answer: Histogram
A histogram displays the frequency distribution of continuous data like repair costs across defined intervals, making it ideal for this purpose.
Question 4: Evidence-based practice in fleet management requires that decisions be based primarily on:
- Vendor recommendations and sales pitches
- Best available research evidence combined with operational expertise and data (Correct answer)
- Technician preferences and past habits
- Budget constraints alone
Correct answer: Best available research evidence combined with operational expertise and data
Evidence-based practice integrates the best available research, operational expertise, and real-world data to guide fleet management decisions.
Question 5: A fleet manager uses a Pareto chart to analyze vehicle defect types. The primary purpose of this chart is to:
- Track vehicle mileage over time
- Identify the few defect categories responsible for the majority of problems (Correct answer)
- Compare two fleets side by side
- Display the average cost of each defect type
Correct answer: Identify the few defect categories responsible for the majority of problems
A Pareto chart applies the 80/20 rule, highlighting the defect categories that account for most of the total defects so efforts can be prioritized.
Question 6: When interpreting a study that claims a new oil additive 'significantly improves' engine life, a critical reviewer should first check:
- The color and packaging of the additive
- Whether the finding is statistically significant and what the effect size is (Correct answer)
- The number of vehicles in the shop that currently use the product
- Whether the additive is available at the local parts supplier
Correct answer: Whether the finding is statistically significant and what the effect size is
Statistical significance and effect size together determine whether a reported improvement is both real and practically meaningful.
Question 7: Fleet key performance indicators (KPIs) serve research purposes by:
- Replacing the need for driver training programs
- Providing quantifiable metrics that enable ongoing monitoring and evidence-based improvements (Correct answer)
- Automating vehicle purchasing decisions
- Eliminating the need for preventive maintenance schedules
Correct answer: Providing quantifiable metrics that enable ongoing monitoring and evidence-based improvements
KPIs provide measurable benchmarks that allow fleet managers to track performance over time and make data-driven decisions.
NCT Research Methods & Evidence-Based Practice 3
A fleet technician notes that fuel efficiency has dropped 15% over six months across 40 vehicles.
To investigate the root cause, the FIRST step in an evidence-based approach is to: