Reliability and Validity Examples: Understanding Consistency in Results

In any scientific experiment or case study, reliability and validity are two crucial aspects that need to be considered to ensure the accuracy of results. One of the key factors in determining reliability is consistency in results or outputs. For instance, let's consider a scenario where we're measuring the average weight of sheep at Taronga Zoo.

To determine whether our results are reliable, we need to look beyond just a single measurement. A sample size of one is essentially meaningless without repetition. We must ask ourselves if our experiment has been repeated multiple times to obtain independent sets of results. Repetition can take many forms, such as repeating the experiment or case study.

When assessing the reliability of an experiment or case study, there are two main aspects to consider: accuracy and consistency. Accuracy relates to how close our results are to benchmark or published results. By improving the precision of our equipment or experimental techniques, we can increase the accuracy of our results. For example, using a measuring balance that provides readings to 4 decimal places instead of one with only 2 decimal places allows for a more precise understanding of the weight.

Experimental technique also plays a significant role in determining accuracy. We may choose the correct equipment but overlook crucial steps in our methodology. For instance, in titration experiments, it's essential to rinse our pipette with the appropriate aliquot solution after rinsing it with water before transferring a new solution into the conical flask. Similarly, when measuring the effect of strong and weak acid on pH levels, we must calibrate our pH probe before moving to a new beaker of water.

To improve the accuracy of length measurements, we can use rulers with narrower increments, such as those with 5cm markings instead of 10cm. The accuracy of our experiment's results can also be affected by the experimental technique or equipment used. For example, using a pipette is generally more precise than relying on a medical dropper to estimate the volume of solution added.

In conclusion, reliability and validity are essential considerations in any scientific experiment or case study. By understanding the importance of consistency in results, accuracy, and experimental technique, we can ensure that our findings are reliable and valid.

Reliability and validity examples