Skip to main content

Table 2 Parameter estimates from the five multilevel regression models examining the associations of LOD with individual-level and state-level variables

From: Why does the adverse effect of inappropriate MRI for LBP vary by geographic location? An exploratory analysis

Parameter

Length of disability

Model 1

Model 2

Model 3

Model 4

Model 5

Intercept

3.835***

3.880***

3.268***

3.269***

3.346***

Gender

 Female

  

0.078***

0.075***

0.040*

 Malea

     

Age (years)

  

0.005***

0.005***

0.005***

Tenure (years)

  

−0.004***

−0.004***

−0.004***

AWW/$100

  

0.017***

0.013***

0.013**

Industry type

 Mining

  

0.452***

0.445***

0.443***

 Construction

  

0.193***

0.183***

0.182***

 Transportation

  

0.258***

0.247***

0.247***

 Agriculture

  

0.090

0.083

0.081

 Manufacturing

  

0.126**

0.118**

0.117**

 Wholesale trade

  

0.084

0.076

0.076

 Retail trade

  

0.127**

0.119**

0.118**

 Services

  

0.101*

0.092*

0.091*

 Public administration

  

0.077

0.069

0.068

 Financea

     

Injury severity

 More severe

  

0.086***

0.085***

0.085***

 Less severea

     

Early opioid/100 mg MEA

  

0.014***

0.014***

0.014***

eMRI scan

 Yes

  

0.426***

0.435***

0.402***

 Noa

     

Lumbar spine surgery

 Yes

  

0.719***

0.715***

0.712***

 Noa

     

Litigation status

 Yes

  

1.144***

1.152***

1.152***

 Noa

     

Median household income ($)

  

−0.007***

−0.007***

− 0.007***

State physician density

 

−0.001***

−0.001*

− 0.001**

- < 0.001

State Orthopedic surgeons density

 

−0.027

0.070

0.070

0.042*

MRI facility rate

 

−0.078

−0.144***

− 0.129***

−0.182***

Wage replacement rate

 

0.002

0.004

0.004

0.004

Waiting period

 

0.052***

0.069***

0.069***

0.069***

Retroactive period

 

0.006**

0.006***

0.006***

0.006***

Treating provider change

 Allowed

 

0.234***

0.115***

0.109***

0.114***

 Allowed once

 

0.001

−0.118**

− 0.116***

− 0.114***

 Not alloweda

     

Treating provider choice

 Allowed

 

0.165***

0.270***

0.261***

0.332***

 Not-alloweda

     

State medical fee schedule

 Yes

 

0.057*

0.100***

0.100***

0.098***

 Noa

     

Unemployment rate

 

0.024**

0.013*

0.012*

0.011

MRI (yes) X State Orthopedic surgeons density

MRI (yes) X State Orthopedic surgeons density

    

0.053***

MRI (yes) X Dr choice (yes)

MRI (yes) X Dr choice (no)

    

0.099**

MRI (Yes) X male gender

MRI (Yes) X female gender

    

−0.047**

MRI (yes) X MRI facility density

MRI (no) X MRI facility density

    

−0.058**

Variance components

 Within-state variability

1.393***

1.390***

0.914***

0.910***

0.910***

 Between-state variability

0.072***

0.035***

0.026***

0.025***

0.025***

 ICC

5%

2%

3%

3%

3%

 Proportional reduction in between-state variability

 

51%

64%

65%

65%

Random slope

 eMRI

   

0.011**

0.011**

Model fit statistic

 -2LL

188,306

188,221***

163,485***

163,323***

163,320*

 BIC

188,310

188,229***

163,493***

163,342***

163,339*

  1. AWW Average weekly wage, MEA Morphine equivalent amount, eMRI Early magnetic resonance imaging, ICC Intraclass correlation coefficient, −2LL −2 log likelihood ratio, BIC Bayesian information criterion
  2. *Indicator of statistical significance p<. 05; **p<. 01; ***p<. 001
  3. aIndicator of reference group