Deborah Mattinson has said Margaret Beckett’s report into why Labour lost the election is a “whitewash”.

The former Labour pollster told the BBC that Beckett’s report is a “massive missed opportunity”. Mattinson expressed concern that “lessons won’t be learned”.

“I can’t see how they will be learned, because [the report] was the vehicle, that was the moment – and if this report didn’t address those issues then I am not sure when they will be addressed”, she said.

Mattinson, who is the founder and the director of research and strategy at BritainThinks, said the voter research she had carried out for the report hadn’t been published. This included research in marginal constituencies such as Croydon, Nuneaton and Glasgow.

“I was somewhat disappointed not to see some of that reflected back. Yes, she picked up on the economy, but there actually was no analysis. It’s reduced down to one bullet point in the report,” Mattinson said.

The report, which was published earlier this week, said that there were four key areas that led to Labour’s defeat:

The leader: Miliband wasn’t seen as strong as Cameron

Economy: the party failed to defeat the myth that Labour was responsible for the financial crash

Labour did’t connect on certain issues such as benefits and immigration

The SNP: the public feared the nationalists would prop up a minority Labour government

Mattinson confirmed a number of these findings. She said the public “didn’t trust Labour to manage the economy” and they “categorically” thought Labour were responsible for the 2008 financial crisis.

She also said the public didn’t think Ed Miliband was “prime ministerial”.

“If you look at every election since the ’70s, what you see is that the party that has the leader with the best ratings is the party that wins. There’s no exception to that,” she said.

However she argue the report She said the report was “quite apologetic, lots of defensive stuff in there – but nothing that really shone a light on what had gone wrong”.