The analysis took in more than five billion FMCG category ad impressions in full-episode player content, which is generally straight-from-TV material longer than 15 minutes.
It found that 93% of mid-roll ads were viewed through to the end, compared to 85% of pre-roll ads and 83% of post-roll ads.
Reasons for non-completion of ads include viewers closing down streams or hiding the video window behind another browser window, according to Vindico UK country manager James Grant.
Vindico, which is part of the group behind Specific Media, allows advertisers to buy, serve, track and measure their online video activity.
It launched in the UK in September 2011.
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