1. Is it clear who ordered and financed the poll?
2. Is there a report documenting the poll’s procedures?
3. Is the target population clearly described?
4. is the questionnaire available and has it been tested?
5. what were the sampling procedures?
* the sample should be drawn for the target population. If it only contains for example people with Internet access, be careful
6. What is the number of respondents?
Many opinion pollers do badly when it comes to predicting elections. This is mainly because they let their respondents self-select them into their polls. So what, who cares? The polls make for some good entertainment and easily fill the talk-shows on television. If everyone knows they cannot be trusted, why care?
We should care. In the Dutch electoral system - with poportional respresentation - every vote counts. If only a small percentage of voters lets their vote depend on the polls of the election result, this can result in shifts of several seats in parliament.