Abstract critiques

1
Abstract critiques

• External, construct, internal

2
Abstract I

• The purpose of this study was to describe the
  change in physical fitness of middle-aged adults
  with an intellectual disability over a period of
  13 years. Participants were 32 adults who worked
  in a supported work environment in Montreal and
  had been participants in a physical fitness study
  in 1983. Using the Canadian Standardized Test of
  Fitness, the participants were evaluated for
  cardiovascular endurance, muscular strength,
  muscular endurance, flexibility, and body
  composition. A home visit prior to the testing
  session refamiliarized the participants with the
  test procedures. Two forms of analysis were used
  to describe the change in fitness over 13 years.
  First, a 2 x 2 (Group x Time) analysis of
  variance for each dependent variable assessed
  change over time. Second, effect sizes were
  calculated to measure the magnitude of change in
  fitness over the 13-year period in comparison to
  those without an intellectual disability. As
  expected, the physical fitness levels of the
  participants were low when compared to those
  without a disability and declined over the 13
  years. In addition, the magnitude of change over
  the 13 years, as compared to those without a
  disability, was greater for male and female
  participants for body mass index and percentage
  of body fat and for female participants for
  cardiovascular endurance and sit-ups. It appears
  that adults with an intellectual disability may
  be particularly at risk for declining health
  associated with aging and low physical fitness.

3
Abstract I. External val.

• Population
• middle-aged adults with an intellectual
  disability
• Sample
• middle-aged adults with an intellectual
  disability
• who worked in a supported work environment in
  Montreal and had been participants in a physical
  fitness study in 1983
• in comparison to those without an intellectual
  disability.
• Setting
• A home visit prior to the testing session
  refamiliarized the participants with the test
  procedures

4
Abstract I. Construct validity

• Dependent variables
• physical fitness
• cardiovascular endurance, muscular strength,
  muscular endurance, flexibility, and body
  composition
• Canadian Standardized Test of Fitness
• Independent variables
• time, gender, intellectual disability
• Relationship
• Change in physical fitness over time
• Questions
• How well is each construct operationalized? Might
  any weakness in the operationalizations alter the
  relationship of interest?

5
Abstract I. Internal validity

• Design
• NEGD
• Pre-test Post-test Non-equivalent groups
  design, with sub groups for gender
• Control over causality
• Temporal precedence, covariance are ok. The
  problems stem from lack of control over
  alternative explanations
• No random assignment, and not clear where other
  non-disabled participants are drawn from (social
  threats?)

6
Abstract II

• It has been shown in classical strength training
  studies using high loads that improvements in
  rate of force development are mainly due to
  adaptations in the intramuscular coordination.
  Adaptations following sensorimotor training were
  also characterized by improvements in the rate of
  force development during maximum voluntary
  isometric contraction. The purpose of the present
  study was to investigate neuromuscular
  adaptations of combined sensorimotor and
  classical strength training. Eighteen subjects
  were randomly assigned to two groups. Group 1
  (SMT-HST) had to perform a period of sensorimotor
  training at first and a high-intensity strength
  training afterwards. Group 2 (HST-SMT) performed
  the high intensity strength training at first and
  the sensorimotor training after. Maximum
  voluntary isometric contraction and neuromuscular
  activation were measured at three occasions
  Before training, after the first, and after the
  second period. The results after the first period
  confirmed the positive effects of both training
  regimen on rate of force development (13
  SMT-HST and 27 HST-SMT, p lt 0.05) and on
  maximum strength (9 HST-SMT and 12
  SMT-HST, p lt 0.05) during maximum voluntary
  contraction. Improvements caused by sensorimotor
  training could only be achieved, when it was
  performed at first. It is supposed that classical
  strength training with high loads basically
  improves the mechanical efficiency of the
  effectors, whereas sensorimotor training alters
  the afferent input on the central nervous system.
  In combination, the sensorimotor training can
  have preconditioning effects on the strength
  training. A combination of both training methods
  can thus be recommended, if the sensorimotor
  training is performed at first.

7
Abstract II. External val.

• Population
• ?
• Sample
• ? 18 participantsno more known
• Setting
• ?

8
Abstract II. Construct validity

• Dependent variables
• Rate of force development
• Maximum strength
• Independent variables
• Time, treatments
• Relationship
• Change in measures of strength as a result of the
  2 treatments
• Questions
• How well is each construct operationalized? Might
  any weakness in the operationalizations alter the
  relationship of interest?

9
Abstract II. Internal validity

• Design
• Pretest-post-test, switched replication,
  randomized design
• Pre-test Post-test Non-equivalent groups
  design, with sub groups for gender
• Control over causality
• Temporal precedence, covariance ok.
• Random assignment used, so multiple group threats
  ok
• Switched replications provide some protection
  against group threats (no compensatory rivalry)