Whilst online research comes with many advantages there are some factors to think about if you are considering the online technique:

Representation

The issue of representation is something to be aware of and is often cited by researchers used to more traditional techniques. Will certain groups be over-represented whilst others are under-represented in your study and will this significantly influence the findings of the research? Will the online technique introduce a bias to your results?

In reality all research methodologies introduce a bias of some sort. The important question is will the bias affect your results to the point where it becomes unreliable to base future decisions on them? If so then you either need to use some controls in your process to recognise and accommodate the bias, employ a secondary methodology to augment the data or not use the online technique at all.

For example, if you are conducting a market intelligence study for a consumer item then would it matter if your final sample contains 75% 18-24 year olds and only 3% aged 70+? If so then action should be taken. This may take the form of employing screening and quotas in your Internet survey, weighting the resultant data, running a paper or telephone based stream for older respondents or deciding to use a different methodology altogether.

If you are running a staff survey then will shop floor workers be properly represented if you only use the online methodology? An alternative paper or telephone version might be needed to run alongside your online survey.

Complexity

With online research, technology is at the heart of the matter and, as we all know, technologies that should make life easier often have a habit of making it harder instead. This may be a problem for your respondents if they are not comfortable with technology or it may be a problem for you as a researcher if you do not have the resources available to produce an online study yourself.

Companies like ORS can manage the entire process of producing and running an online study for you so this is not an insurmountable problem.

You should be sure though that the use of technology will not significantly impact the ability of your audience to respond, particularly an audience with disabilities or other special needs. If you are working with these groups then you should ensure that your online surveys confirm to the W3C Web Accessibility Initiative guidelines.