NPRC Survey of Customer Satisfaction

NPRC Customer Satisfaction Survey Sampling Plan
Overview
In order for the results of the NPRC to reflect a truly random sample of NPRC's customers, a protocol must
be established to identify each member of the customer universe to have a unique probability of selection.
Synovate will provide NPRC with a list of 1000 IDs to be assigned to individuals receiving record request
responses over the course of the three month field period. A designated NPRC employee will select the
response packages into which to insert the surveys and business reply envelopes. The envelope stutter will
insert these materials and complete the Excel spreadsheet with the necessary information for each sampled
individual. NPRC will deliver the Excel sheet with the information for each ID/sampled individual to
Synovate every Monday morning with the data for the previous week (Monday through Friday).
Sampled Individual Selection
Synovate will provide the NPRC selector with the following guidelines for selecting sampled individuals each
day of the week:
•

The number of individuals to select on that day,

•

The interval at which to select individuals,

•

The shipment with which to begin on that day.

For example, on Monday, the selector should select every 200th individual, starting with the 190th outgoing
package. Fifteen surveys should be inserted, which would require 3,990 packages be shipped that day.
With this methodology, the 1000 surveys will be distributed over the scheduled field period. There are 57
workdays in the October- December (assuming 3 weekdays are excluded as a holidays: 10/10, 11/11,
11/24, and no data collection is done in the last week).
Day

#selected

Number to

Interval at which to

Estimated number of

per day

start on

select individuals

shipments

Monday

19

190

200

3990

Tuesday

16

12

200

3212

Wednesday

16

130

200

3330

Thursday

19

198

200

3998

Friday

18

209

200

3809

processed

NOTE: THE SAMPLING PLAN CANNOT BE FINALIZED UNTIL NPRC CONFIRMS THAT THE
ESTIMATED NUMBER OF SHIPMENTS PROCESSED FOR EACH WEEKDAY IS APPROXIMATELY
ACCURATE (OR PROVIDES CORRECT INFORMATION IF INACCURATE).
Adjustments
The sampling plan will be reviewed after October 29th to determine whether it is accurately reflecting
NPRC's workflow or needs changes to be made.