Direct mail and email generated the best return on investment among media channels in 2006, according to respondents - both B2B and consumer marketers - to a new Harte-Hanks survey administered by CSO Insights, reports MarketingCharts.

Among business-to-business marketers, digital marketing - email, websites and online registrations, and search - are seeing increased investments, but a "continuing struggle with data quality" is a "major roadblock to success," the study found.

Meanwhile, consumer marketers point to a lack of data quality - currency and accuracy - as hurting marketing efforts, though marketers gave higher marks for data quality than they had in a previous survey two years ago, according to the findings of "Target Marketing Priorities Analysis: 2007 Key Trends."

Among all media, digital media categories - with the exception of paid search - receive the highest priorities, with near-equal attention given to data analysis, among other data-related concerns.

In both B2B and consumer markets, prompt action based on data analysis is a top priority for business demand generation, the study reported.

MarketingCharts provides more data from the study.