Almost half of peak time trains between Fife and Edinburgh were either late, overcrowded or skipped stops at the end of last year.
A total of 720 of the 1,597 services that ran – or 45.5% – faced some kind of disruption, according to official ScotRail figures.
Fife MSP Claire Baker has now arranged to quiz Abellio ScotRail on behalf of angry commuters over its running of the Fife Circle.
The railway operator has agreed to be questioned by the Mid Scotland and Fife MSP during a live Facebook chat on Monday.
She will pose questions submitted by local people, both in advance of and during the chat.
The lunchtime event will involve the Labour politician, ScotRail’s chief operating officer Angus Thom and head of integrated control Mark Ilderton.
The question and answer session was organised as the new statistics revealed the true extent of the disruption facing commuters.
There were 434 disruptions to morning and evening peak time services between Edinburgh and Kirkcaldy out of 940 trains that ran towards the end of last year.
At the same time, there were 286 disruptions during morning and evening peak time services out of 657 trains that ran between Cardenden and Edinburgh .
Of the 940 Edinburgh services via Kirkcaldy, 354 were late, 29 were cancelled, four failed to stop and 47 were short formed, which means they did not contain the number of seats set out in the contract with the Scottish Government.
This resulted in disruption to commuters on 46% of all services.
Of the 657 Edinburgh services via Cardenden, 225 were late, 35 cancelled, one failed to stop and 25 were short formed.
This meant disruption to 43% of those trains.
Urging commuters and constituents to get in touch with questions, Mrs Baker said: “My parliamentary inbox is regularly full of complaints from commuters across Fife and has been for a number of years.
“We are seeing the consistent late running of services, stop skipping and trains regularly running with fewer carriages leading to packed and uncomfortable commutes. This has to change.”
ScotRail said only five of the 1,597 trains quoted by Mrs Baker had skipped stops, a tactic used only at times of severe disruption in a bid to minimise impact on the entire network.
A ScotRail Alliance spokesman added: “The introduction of our new trains and the electrification of the central belt will allow us to make best use of our existing fleet and make positive changes in Fife.
“Mr Thom and Mr Ilderton are looking forward to meeting with Claire Baker.”