Allan Kozlowski, PhD, BSc(PT)
Director of Outcomes Research
Mary Free Bed Rehabilitation Hospital

Keith Lohse

Keith R. Lohse, PhD
Assistant Professor
University of Utah College of Health


An Introduction to Longitudinal Data Analysis (Part I) IC15



Allan Kozlowski, PhD, BSc(PT)
Director of Outcomes Research
Mary Free Bed Rehabilitation Hospital

Keith Lohse

Keith R. Lohse, PhD
Assistant Professor
University of Utah College of Health


DAY Saturday 13 April 2019

TIME 9:00 AM – 1:00 PM

FORMAT 4-hours instructional course, Interactive Lecture


TOPIC AREAS Measurement, Brain Injury, Spinal Cord Injury, Stroke

CAREER LEVEL  Introductory

PART II  Follows from 2:00 PM – 6:00 PM Read More >>



Researchers and Clinicians from any discipline interested in longitudinal modeling


Course Description

Rehabilitation researchers and clinicians often deal with outcomes that evolve over time and are not suited to binary categorization of pre- post-assessments, as is common in other areas of medicine and healthcare. Current methods of outcome evaluation typically examine group averages as difference scores at the facility level, and treat individual differences as measurement error. In a healthcare environment where concepts of patient centeredness and value-based care are gaining attention, we need methods to examine rehabilitation outcomes that span services and offer interpretability for individual patients. Fortunately, advanced statistical methodologies are available to accurately model longitudinal data as continuous outcomes for groups and individuals. An advantage of such models is the retention of information on individual differences, which allows the generation of individual-level trajectories and the potential to predict patient outcomes. Another advantage is found in the capacity to make group comparisons on the rate of change, such as in testing for treatment effects in a randomized controlled trial applied during recovery. Conversely, standard regression methods including repeated measures analysis of variance, describe groups but not individuals, test for mean differences, do not explicitly incorporate time, and do not adequately account for correlations and covariances that exist in multi-time point data. Additionally, the individual growth curve model can accommodate data that was collected at different times, and participants can have difference numbers of data points, assuming data are missing at random. This instructional course will provide an introduction to these methods in regard to continuous outcomes that evolve over time for observational and randomized study designs. Topics to be discussed include the conceptual basis for the individual growth curve model, how it differs from other regression models, processes for examining longitudinal data and determining a best-fit trajectory, and methods for evaluating covariate associations with trajectory parameters including hypothesis testing for rate of change. Following the course, learners will be able to appraise existing data for suitability to an individual growth curve model, discuss the relevance of such models with statistical consultants, and plan for data collection in future projects which are suited to modeling outcomes longitudinally.



Upon completion of the course, participants should be able to:

  1. Identify circumstances in which longitudinal mixed-effects regression (LMER) models are appropriate
  2. Discuss measurement issues in rehabilitation related to LMER
  3. Describe a process for examining longitudinal data and determining a best-fit trajectory
  4. Describe a process for evaluating covariate associations with trajectory parameters

CME/CEUS 4 Hours

ACRM Training Institute registration includes CME/CEUs for the following disciplines:

  • Case Managers (CCMC)
  • Disability Management Specialists (CDMS)
  • Healthcare Executives (ACHE)
  • Nurses (ANCC)
  • Occupational Therapists (AOTA)
  • Physical Therapists (FSBPT-24 states)
  • Physicians (ACCME-CME)
  • Psychologists (APA Division 22)
  • Rehabilitation Counselors (CRCC)
  • Social Workers (NASW)
  • Speech Therapists (ASHA)


4 hours of live instruction, continuing education credit processing, access to presentation slides (if provided by presenters), NON-ACRM members receive introductory 6- month membership.



Early Bird rate $49 for members and $99 for non-members      and that includes CME / CEU processing. See the rate tables here.

We encourage you to register early      before tickets are gone. Don’t say we didn’t warn you.

Limited space available


The secret sauce for your career


Discounted for ACRM members, the ACRM Spring Meeting offers instructional courses with continuing education credits in your choice of up to 11 disciplines.

Jump in, get involved, meet and work with ACRM members face-to-face in a casual setting. This event is all about getting research into practice in a supercharged atmosphere and a friendly, collaborative, and inspiring environment.


28+ instructional courses. Scroll + see the agenda…

The ACRM Spring Meeting is a venue for face-to-face collaborating of many interdisciplinary ACRM community groups and committees — the heart of ACRM. Come find your tribe and become a member of the vibrant ACRM community.


Ridiculously inexpensive? Yep. That’s because we believe in getting the research to practice ASAP. And we think that having a low-cost to attend is a good way to do that.

Early Bird rates are as low as $49 for members and $99 for non-members — and that includes CME / CEU processing. Are you kidding me?!? Nope. See the rate tables here.

We encourage you to register early — before tickets are gone. Don’t say we didn’t warn you.


You’re our people

ACRM attendees are all kinds of rehabilitation professionals — from researchers to clinicians (including
doctors, nurses, PT assistants, hospital administrators to name just a few) to consumers, family, caregivers, and
more. Everyone is invited and warmly welcomed at ACRM.

They span a wide spectrum of experience from students to well-seasoned pros and hail from the largest
rehabilitation institutions and universities to one-person solopreneurs.
Attendees at previous ACRM events include designers, art directors, and production staff from hundreds of
institutions, companies, and universities from all around the world, including:



This place is beautiful. The Hilton Chicago is the optimum headquarters with superb onsite amenities + easy access to the best of Chicago.

  • SAVE TIME — staying right in the ACTION the ultimate venue for efficient collaboration
  • SAVE MONEY — book your room through ACRM and SAVE
  • CONVENIENCE — you are only an elevator ride away from courses and meeting and located right on the famed Michigan avenue — smack in the middle of city hotspots — Grant Park, museums, Navy Pier, and more
  • HEALTH CLUB — on the 8th floor, it’s the largest hotel gym in Chicago with indoor pool and hot tub an indoor running track, strength training and cardio equipment, Synergy 360, and sundeck with views of the Chicago skyline.
  • HHONORS Club — join the Hilton Honors through the ACRM Fast Track to GOLD program and get EXTRA points and all the cool member benefits including digital check-in.
  • Get the HHONORS APP — TIP: It’s really VERY handy

BOOK NOW to enjoy the SAVINGS and CONVENIENCE of staying on-site at the headquarters hotel.

Or book Hilton by phone: +1.877.865.5320
with Booking Code: ACR to ensure the lowest rates
(Code: ACT for Government booking)

Space is limited. So lock in your seat and REGISTER TODAY >>