Editor's note: Greg Ryan is owner of Ryan Consulting. He can be reached at ryan.greg@comcast.net.

Picture for a moment (if you will) the time, effort and money spent to build a survey draft, field it, tabulate and analyze data – only to find that the final overall metrics or scores the researcher used were faulty or misleading.

Not only has the researcher wasted their effort and their client’s money but perhaps more importantly, they have squandered respondents’ valuable time, to say nothing of the cost of incentives, etc.

Why is choosing the right customer metric so important to researchers? (In this discussion, when we say “customer metric” we are referring to overall customer satisfaction or customer loyalty metrics.) Many companies place great emphasis on KPIs like overall satisfaction or loyalty scores and include them in their corporate goals and compensation and/or bonuses. But what if the system of gathering and measuring these corporate goals and the resulting employee compensation was flawed? Not a good predicament to be in.

There are two metrics, which incorporate a five-point scale, that have been used for many decades without problems or flaws (provided the research is done correctly): the “gold standard” American Customer Satisfaction Index (ACSI) customer satisfaction question – “How satisfied are you with the following product/service?” – and also a standard loyalty metric question – “How likely are you to purchase X products or services in the future?”

I was employed as a research consultant for nearly four years at Kaiser Permanente, where I was responsible for research, metrics and executive interface for its largest lines of business (national accounts, strategic accounts, labor and trust, etc.). When I first joined Kaiser, executives were complaining that Kaiser’s Net Promoter Score (NPS) appeared to be very unpredictable. I informed them that NPS was a volatile  met...