A journal article from the American Association on

Intellectual and Developmental Disabilities

Presented by Dave BertleffYoungstown State University

Goal: To identify risk factors for falling in adults with intellectual disabilities.

Method: Use multinomial logistic regression to compare relationships between a non-metric dependent variable and metric or dichotomous independent variables.

Will compare groups through a combination of binary logistic regressions.

The scale used to assess risk of fall in elderly persons with intellectual disabilities for this study and several others is called the Tinetti Instrument:

Balance test – 9 items (max score 16)

Gait test – 7 items (max score 12)

25 was determined as cutoff point

Below = “Fallers”

Above = “Nonfallers”

Data was then gathered from medical records regarding IQ, complicated conditions, and medications of the participants

Univariate analysis to determine ability to predict risk of fall

Then, variables with sig. levels < .05 entered into multivariate analysis

Parameter Odds Ratio 95% CI X2

Gender (male) 0.85 0.41-1.75 0.20Age ≥ 50 years 2.46 1.17-5.15 5.8*Epilepsy 4.64 2.15-10.02 16.42**Paretic conditions 22.82 8.13-64.09 49.40**Antipsychotics 0.95 0.45-2.00 0.02Anticonvulsants 4.19 1.93-9.07 14.03** After adjustment for the presence of epilepsy 1.72 0.48-6.17 0.69Benzodiazepines 2.03 0.91-4.52 3.02Antidepressants 0.40 0.05-3.47 0.18Level of intellectual disability: severe, or profound (IQ ≤ 34)

1.87 0.59-5.94 1.14

Stratification of the participants based on presence or absence of epilepsy eliminated impact of anticonvulsants on the risk of fall

Variables to be used in multivariate analysis: Age Epilepsy Paretic conditions

Multinomial Logistic Regression used with Faller/Nonfaller as the dependent variable

In SPSS, the “Factors” box is where the dichotomous variables, epilepsy and paretic conditions, are placed

The “Covariates” box is where the metric variable age is placed

Running the regression gave the following results…

Parameter

Odds Ratio

95% CI X2

Age 1.06 1.01-1.11 6.02*Epilepsy 6.55 2.33-18.38 12.74**

Paretic Condition

30.98 9.21-104.16

30.80**

* p<.05 **p<.001

All three are independent risk factors for falls in adults with intellectual disabilities

Data shows risk of fall increases by 1.06n times over n years. (n=12 >> 2 times)

Presence of paretic conditions was most evident risk factor

American Association on Intellectual and Developmental Disabilities

G. Rodriguez, Multinomial Response Models, Chapter 6