There have been 13 video assistant referee (VAR) mistakes in the Premier League so far this season - down from 20 at the same point last term - say league bosses.

Four incorrect VAR interventions and nine missed interventions from the first 23 rounds of games have been found by the competition's Key Match Incidents (KMI) panel.

There have been 70 VAR interventions in 239 league games this season - around one every three matches.

The league says the accuracy of 'Key Match Incidents' is at 96.4% - up from 95.7% at the corresponding point last term.

"Nobody here underestimates the significance and the impact of one single error," said chief football officer Tony Scholes.

"We know that one single error can cost clubs. Points and results can cost managers positions, potentially players their place."

In Erik ten Hag's case, that was literally what happened - one of the four mistakes was the penalty given against his Manchester United side in what proved to be his final match in charge.

Referees have also been subject to abuse, with police recently investigating "threats and abuse" directed at Michael Oliver following Arsenal's 1-0 win over Wolves in January.

Oliver controversially sent off Gunners defender Myles Lewis-Skelly - a decision that was later reversed on appeal.

Former referee David Coote was sacked by the referees' body in December after a "thorough investigation" into his conduct.

Asked about trust in officials, Scholes said: "We all have a responsibility to have some balance in the comments that are made.

"We cannot have the officials, such a key part of a successful and entertaining league, facing the kind of abuse that occurs on occasion.

"These guys are good. I know that is not always the perception, but the rest of the world recognises how good they are."

The Premier League declined to list the nine missed interventions but did outline the four errors to the media.

What were the four VAR errors?

Outtara 'handball' - Bournemouth 1-1 Newcastle, 25 August

• What: Dango Outtara thought he had scored a late winner for Bournemouth when he jumped to head the ball. The goal was given by on-field referee David Coote.
• Decision: VAR Tim Robinson advised Coote to reverse his decision, deeming it to be handball. As he deemed it a factual decision rather than subjective, he did not send Coote to the monitor to review it.
• Outcome: With no conclusive evidence as to whether the ball was low enough on Ouattara's arm to deem it a handball, PGMOL chief Howard Webb - speaking on Sky Sports' Match Officials Mic'd Up - said VAR was incorrect to intervene.

De Ligt foul on Ings - West Ham 2-1 Man Utd, 27 October

• What: West Ham striker Danny Ings went down inside the penalty area while challenging for the ball with Manchester United defender Mathijs de Ligt. Referee David Coote waved play on but was advised by VAR Michael Oliver to review the incident on the pitchside monitor.
• Decision: Coote awarded a penalty, which Jarrod Bowen scored to give West Ham victory.
• Outcome: Under-pressure Man Utd manager Ten Hag was sacked the next day. Webb later said the Hammers should not have been awarded a penalty.

Noorgard red card - Brentford 0-0 Everton, 23 November

• What: Brentford's Christian Noorgard caught Everton goalkeeper Jordan Pickford on the knee while challenging for the ball in the penalty area.
• Decision: Referee Chris Kavanagh did not take action but was advised by the VAR to review the incident. He subsequently showed Noorgard a straight red card.
• Outcome: Norgaard's three-match suspension for serious foul play was overturned by an independent panel on appeal.

Milenkovic goal disallowed - Nottingham Forest 3-2 Southampton, 19 January

• What: Nikola Milenkovic scored a header to put Nottingham Forest 4-1 up.
• Decision: The VAR advised referee Anthony Taylor to disallow the goal as Forest striker Chris Wood came from an offside position and impeded the Southampton defenders to challenge for the ball. Wood did not touch the ball.
• Result: An independent panel found the goal should have been given.

'Significant progress' on semi-automated offside technology

It had been hoped semi-automated offside technology, which is used in Fifa and Uefa competitions, would be introduced in either the October or November international windows.

League officials hope it would reduce the time taken to check offsides by 31 seconds.

Scholes, despite his own misgivings, says there has been significant progress over the past "four to six weeks", and the intention is still to bring it in this season.

"This technology doesn't improve the accuracy, it makes the process more efficient," he said.

"Why wouldn't you introduce it if you are absolutely confident it is ready?"