The 3 Ingredients of a Good Test
Are you testing _____?!
I think we’ve all had that discussion with a colleague or taken a stroll through social media that leaves a pit in our stomach. Are we missing the boat by not including (insert assessment)? We rush into the clinic to add this new assessment only to realize you don’t have the time to include the testing battery into your session, have your boss give a thumbs down to a new equipment purchase, or simply have no idea what to do with the information.
Assessment is the first step to orienting your interventions in the right direction. With this all important step, how do we decide what information is worthwhile and what is simply noise? How do we determine what is right to guide the clinicians model? How do we find good tests that work within the constraints of our environment?
There are three main qualities to a useful assessment that help you to decipher good data collection from information that can cloud your judgment. A good assessment should be logistically feasible, valid and reliable, and practically applicable. There are certainly times to use assessments that check only one or two of these boxes, however, our cornerstone tests should satisfy these criteria. Let’s break these down further…
Logistically Feasible: Simply put, can you run this in your clinic without breaking the bank or derailing a client’s entire session. Force plate testing may be useful for gaining information on many different qualities, but if this equipment doesn’t fit into your clinic’s budget or current level of expertis, it is simply not feasible. Another assessments lengthy testing battery may be valid and reliable in the literature but the 40 minutes it will take to complete the testing may not be worth spending one of your patients 6 approved visits on (looking at you CIGNA….)
Example: Lateral Step Down Test
Features: Requires only a box/step and takes 1-2 minutes to complete.
Valid and Reliable: Has the test been put to the fire in research? A test meeting this criteria must have sufficient backing in the literature to demonstrate that the test is both valid (does the test actually measure what it is supposed to measure?) and reliable (when I check this again, can I count on the fact that the results can be reproduced?). Without this backing, the data we glean will be misleading.
Example: Isokinetic Testing
Features: Highly studied test across a wide number of cohorts/conditions. Considered the “Gold Standard” isolated torque assessment.
Practically Applicable: How does the results of this assessment guide your clinical process? Do the results influence your programming decision making or is the result just nice to have? The practical applicability of a test is related to how the information fits into your clinical process. An assessment may not be validated in the literature but through your clinical experience and pattern recognition, it can be extremely informative. On the other hand, a test can have stacks of research backing it but the information gleaned may not directly aid decision making.
Example: Hop Testing
Features: The battery of hops can help the clinician distinguish between continued areas of limitation (i.e propulsion, landing, or elasticity issue?). Within a specific clinical decision making process, the test can inform next step in exercise. This provides additional practical applicability over simply providing limb symmetry index or confirmation of return to play readiness.
Example of a test checking all three boxes: Anterior Reach Y-Balance
Logisitcal Feasibility: Takes no more than 3-4 minutes with warmups. Can use Y-Balance kit or tape and a furniture glider.
Valid and Reliable: Thoroughly studies across a wide range of populations and conditions. Well established normative values for many population.
Pratical Applicability: Multiple studies examining injury risk implications. The assessment constrains a pattern (Ankle dorsiflexiion/Anterior tibial translation) that is often limited following many lower extremity injuries. Inability to perform this well may lead to further breakouts for range of motion, strength, or coordination limitations.
As clinicians, our cornerstone tests should be live at the interaction of logistical feasibility, validity/reliability, and practical applicability. There will certainly be times that where utilizing tests that only check one or two of these criteria will be appropriate. Clinical practice must be fluid and adaptable to the constraints of the environment, the patient, and the level of understanding of the clinician. Our testing choices must match these constraints. When choosing a test, ask yourself how will this work logistically within my setting? Is this assessment supported within the literature for the population and presentations I am seeking to use it for? And finally, how will the results of this test influence what I chose to do next with this client.
Do not fall into testing FOMO (fear of missing out). Use your testing with precision to meet the n=1 reality of you and your client.
– Anthony Iannarino, PT, DPT, CSCS
Read: Kinesiology of the Musculoskeletal System: Foundations for Biomechanics By: Donald Neumann
- Reminder to self: Go back to foundational biomechanics regularly. PT students probably want to slap for this one me right now and established PT’s may need to get the dust rags out for this one but it really is a phenomenal resource.
- Jarrod Antflick is a performance/medical consultant across many professional sports and a tendon researcher. In this episode, Jarrod provides some key insights into tendon performance principles and evaluation.
- Cory is the Head of S&C with the Phoenix Suns. His page is full of useful training tools and behind the scenes looks into high performance in the NBA.
- A look at whether tendon stiffness is appropriate to achieve an optimal efficiency in various muscles.