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Annex B - Mystery Shopping Methodology

B1. All calls were conducted in accordance with the guidelines outlined by the Market Research Society and ESOMAR. Callers did not reveal their identity either during the call or at the end to ensure the continued objectivity of the whole research project. DQ providers worked with Ofcom and ICSTIS to ensure that the study was as representative of the 'real world' profile of calls to DQ services. As such they were aware that Ofcom and ICSTIS were conducting a further mystery shopping exercise, but were not aware of the precise timing and details in order to protect the study's objectivity.

B2. Calls were initially recorded on a simple, easy to use paper script which allowed flexibility in recording data, and the order in which questions during the call were posed and answered. During the call, all time information was recorded using digital clocks and measured to the nearest second. Data recorded during these calls were then transferred on to a CATI (Computer Aided Telephone Interviewing) system from which subsequent analysis was run.

The majority of calls were made from MORI's central telephone centre in Scotland, calls were made from landlines. In addition, where directory enquiries were requested in the Welsh language, a Welsh speaker was used.

Call profile

B3. To attempt to reflect the approximate spread of calls received by directory enquiry call handlers, calls were made to DQ operators throughout the day and at weekends. The times were as follows:

Daytime (9am - 5pm) c61%
Evening (5pm - 10pm) c21%
Late Night (10pm - midnight) c2%
Weekends (10am - 6pm) c16%

B4. The scenarios used in the study were:

• Business: requesting the telephone number of a UK business. A range of businesses spread across the country were requested.
• Residential: the telephone number of a UK resident, giving the full name and address. A geographic spread of numbers was requested.

B5. Both residential and business requests were designed in order to represent 'easy - potentially dealt with in under 60 seconds', or 'difficult - potentially dealt with in at least 60 seconds' scenarios. 'Difficult' requests consisted of, either difficult spellings, unusual businesses, or information being withheld from the call operator until prompted. The scenarios were consistent across all calls to all DQ numbers.

Provision of numbers to be requested

B6. All numbers to be requested were provided by OSIS, the central database for all residential and business landline numbers. This is part of BT's Wholesale Directory Services operation. Because of concerns that BT might be able to favour its own DQ service, BT signed a confidentiality undertaking in respect of the information which it handled in respect of the mystery shopping exercise.

B7. On completion of fieldwork all numbers were re-verified by OSIS. One residential number had been withdrawn during fieldwork and as such data for this scenario was discounted in all cases, resulting in a total reduction of 120 residential requests.

B8. In the case of business requests, if the number provided did not match the number (or numbers) expected, they were checked (by calling them) to ascertain whether or not it was a suitable alternative.

Types and proportion of requests

B9. In total 5880 requests were made, spread across 30 national DQ numbers, and different times of the day (weekday and weekend). The same requests were made to each supplier at four different intervals during the day.

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