Methodology/Data Collection

The program is a comprehensive measurement of the retail dispensing market among optical retail outlets in the U.S. It employs multiple data collection methodologies in order to obtain the most accurate sales information from a representative sample of eye care professionals (ECP's).

Wherever they are available, electronic records from the store or chain’s EPOS system are collected. In some of the independent outlets where EPOS data are not available, dispensing doctors and store personnel maintain specially designed logbooks in which they record the information on fits and sales that we require. All data are captured at the individual by UPC/SKU allowing for all levels of total and sub-total to be provided in the reporting phase of the program.

Sample Size and Design

The base sample for this program has recently been expanded to include almost 3,500 shops across the United States. This sample is then extrapolated to the total universe of about 37,000 optical retail outlets that sell contact lenses. The program employs a disproportionate, stratified sampling technique which over-samples the larger-volume outlets (i.e. national and regional chains) and then corrects for this factor in the weighting process to yield the final projections. Such a technique offers the dual benefits of decreasing standard sampling error in the key stratum of high-volume clinics as well as increasing overall sampling efficiency.

Products Reported

The program includes measurement of all brands, types and forms of the product categories being measured. 

Metrics Provided

Standard program elements include the following for the total category, manufacturer, brand, type, design, etc. (per all key product attributes and classifications within the GfK global codeplan):

Measures

• Sales in units, lenses and value
• Shares of units, lenses and value
• % of Stores Selling – unweighted and weighted
• Average prices
• Sales per shop 

 Geographic Areas

• Total U.S.
• Four (4) U.S. Census Regions

 Type of Retail Operation

• National Chains
• Regional Chains
• Independents

Frequency

• Calendar months

Deliverables 

The primary deliverable vehicle is the GfK StarTrack™ Explorer (GSE) system, the highly flexible and powerful proprietary GfK data storage, retrieval and analysis tool for all countries within the GfK worldwide Optics Program. GSE's key features include:

• Fully Global in Scope
• Web Accessible – 24/7/365
• Consistent Codeplan Across All Countries
• Common Product Identifications/Definitions
• Earlier Availability of Data
• Data Always Current & Up-To-Date
• Scalable: Ability to add more data, more users, more access servers, more database processors
• No Client Infrastructure Investment
• Tabular and Graphic Outputs
• Easy Transportability to Microsoft© Office Programs