Table: Methodological and Sampling Changes to National Immunization Survey, 2011 

Step Brief Description 

Changes from Previous 

NIS Weighting? Comments 

1 Base Weights No 

2 Adjustment for Non-resolution of Phone Number No 

3 Adjustment for Cell-Phone Status Screener 

Nonresponse 

Yes Screener to restrict cell sample to cell-phone only/cell-phone mainly; 

applies only to Q1/2011 cell sample (this step is not needed for 

Q2/2011-Q4/2011 cell sample) 

4 Adjustment for Age Screener Nonresponse No 

5 Adjustment for Subsampling of Teens No NIS Teen only 

6 Adjustment for Interview Nonresponse No 

7 Adjustment for Multiple Phone Lines No 

8 Annual Weights Yes Landline sample is combined as usual to derive the annual landline 

sample weight. The 4 quarters of cell sample are combined by 

estimation area and telephone status. 

9 Adjustment for Children or Teens with HH 

Interview Completes to Combined Landline, CellPhone, No Phone Population 

Yes 

NIS: Based on minimizing the MSE for the number of children that are 

breast fed, cell only children from the cell sample are combined with 

proxy cell only children from the landline sample; based on effective 

sample size, cell and landline dual user children from the cell sample are 

combined with cell and landline dual user children from the landline 

sample. Landline sample children with service interruption are adjusted 

to represent no phone children. 

NIS Teen: Based on minimizing the MSE for the number of teen with a 

household report of receiving any varicella shots, cell only teens from 

the cell sample are combined with proxy cell only teens from the 

landline sample; based on effective sample size, cell and landline dual 

user teens from the cell sample are combined with cell and landline 

dual user teens from the landline sample. Landline sample teens with 

service interruption are adjusted to represent no phone teens. 

10 Trim the Combined Cell and Landline Sample 

Weights 

Yes Within each estimation area, weights larger than median plus six times 

Interquartile Range (IQR) are trimmed 

11 Adjustment to Population Control Totals Yes Trimmed weights are adjusted to total population controls by 

estimation area 

12 Post-stratification No 

13 Raking to Population Controls (yields RDD 

weight) 

Yes Add telephone status (cell-phone-only, cell and landline dual user, 

landline-only, no phone) as first step in raking 

14 Adjustment for Provider Nonresponse Yes Include sample type (landline, cell-phone) in the propensity model along 

with regular covariates, include first-order interactions of sample type 

with covariates 

15 Adjustment for Children with Adequate Provider 

Data to Combined Landline, Cell-Phone, No 

Phone Population 

Yes 

NIS: Based on minimizing the MSE for the number of children that are 

up-to-date for 4:3:1:3:3:1, cell only children from the cell sample are 

combined with proxy cell only children from the landline sample; based 

on effective sample size, cell and landline dual user children from the 

cell sample are combined with cell and landline dual user children from 

the landline sample. Landline sample children with service interruption 

are adjusted to represent no phone children. 

NIS Teen: Based on minimizing the MSE for the number of teens that 

are up-to-date for 1+ MenACWY, cell only teens from the cell sample 

are combined with proxy cell only teens from the landline sample; 

based on effective sample size, cell and landline dual user teens from 

the cell sample are combined with cell and landline dual user teens 

from the landline sample. Landline sample teens with service 

interruption are adjusted to represent no phone teens. 

16 Raking to Population Controls (yields provider 

weight) 

Yes Add telephone status (cell-phone-only, cell and landline dual user, 

landline-only, no phone) as first step in raking