How Is the CASC Marked? Pass Mark, Borderline Regression and the 12-Station Rule

"How is the CASC marked?" is one of the most common questions trainees ask, and it is easy to see why. You are about to spend seven minutes at a time being observed by an examiner who is writing things down, and nobody can see the page. This guide explains, in plain language, how the MRCPsych CASC is scored and how the pass mark is set, based on the Royal College of Psychiatrists' published guidance.

Always check the current Royal College guidance and marksheets before your sitting, because details can change between diets.

The Short Answer: Two Conditions You Must Meet

To pass the CASC you must satisfy both of these:

• •Reach or exceed the total borderline regression score for your exam day
• •Pass at least 12 stations

Meeting only one of them is not enough. A candidate who scores well overall but passes fewer than 12 stations does not pass, and a candidate who passes 12 stations but falls below the total score does not pass either. The two rules together are designed to make sure that you perform acceptably across the full breadth of core training, not just in your favourite stations.

How Each Station Is Scored

At every station the examiner gives you two kinds of mark:

• •Analytic domain scores: the examiner scores three to five domains for the station, each from 1 (Poor) to 5 (Excellent). Domains typically cover things such as building rapport, the range and depth of questioning and how well you meet the task of the station.
• •An overall global judgement: one of six grades — Excellent Pass, Pass, Borderline Pass, Borderline Fail, Fail or Severe Fail.

The domain scores are weighted and add up to your station score. The global judgement is a separate, holistic view of your performance. You do not see either mark on the day.

What Is Borderline Regression?

Borderline regression is the standard-setting method the College uses to decide the pass mark. It sounds technical but the idea is simple:

1. For each station, the examiners' weighted domain scores are plotted against their global judgements.
2. A line of best fit is drawn through those points.
3. The domain score that sits on the line at the "borderline" grade becomes the pass mark for that station.
4. The pass mark for the exam day is the average of the station pass marks for that day.
5. A standard error of measurement is added, which raises the bar slightly. This reflects the policy of passing only candidates who are clearly competent.

In practice this means the pass mark is not a fixed percentage. It is built from how examiners judged real candidates on the day, so a harder station has a lower pass mark and an easier station has a higher one.

A Borderline Fail Does Not Mean You Failed the Station

This is the point that surprises most candidates. The global judgement is used to set the pass mark, not to decide whether you passed a given station. You pass a station by reaching that station's cut score, and it is possible to pass a station even if the examiner's global judgement was Borderline Fail.

So if you leave a station convinced it went badly, you may well have passed it. Do not carry that worry into the next room, because every station is marked independently.

The 12-Station Rule

The 12-station minimum is based on station cut scores, not on global judgements. Because station difficulty varies, there is one overall minimum rather than a separate threshold for each station type.

The College's reasoning is that passing 12 stations shows acceptable performance across a broad range of scenarios, which reflects the breadth of the curriculum. If you can pass 12 of 16, you have shown that you are safe and competent across most of what a core trainee is expected to do.

What a Borderline Candidate Is Expected to Pass

The College gives a useful picture of the standard. A borderline candidate is expected to pass roughly:

• •8 of the 10 history-taking and examination stations
• •4 of the 6 management stations

This tells you something important about how to prepare. You do not need a perfect score at every station. You need to be reliably competent at the core tasks — history, mental state, risk, cognitive and physical examination — and to hold your own in the harder management and communication stations.

Why Two Severe Fails Are Dangerous

Two or more Severe Fail judgements trigger a review of your overall performance by the Examinations Committee. In that situation a candidate can fail even if their total score and station count would otherwise be enough.

A Severe Fail is not about missing a few marks. It reflects serious concerns, for example unsafe practice, a failure to address an obvious risk, or unprofessional behaviour towards the patient. Protect yourself by always addressing risk, being respectful, and never giving false reassurance.

Timings: Reading Time and Task Time

Each station gives you seven minutes for the task. Reading time differs by circuit:

• •Morning circuit: 4 minutes of reading time, then 7 minutes for the task
• •Afternoon circuit: 90 seconds of reading time, then 7 minutes for the task

Practise with the shorter reading time. Learning to read a station instruction, form a plan and walk in calmly within 90 seconds is a skill in itself.

What This Means for Your Preparation

Understanding the marking scheme should change how you practise:

• •Cover every domain, every time. Rapport, structured questioning and meeting the station's task all carry marks. A station you rush through with no rapport loses marks even if the clinical content is good.
• •Aim for consistency, not brilliance. With a 12-of-16 rule, a solid pass at every station beats a spectacular pass at six and a collapse at four.
• •Never skip risk. It protects you from the Severe Fail review and it is marked in many stations.
• •Use the marksheet to give feedback. When you practise with a partner, score each other from 1 to 5 on the domains and give a global grade. Our AI-powered stations in the CASC Master app give examiner-style domain feedback in the same spirit.
• •Do not stop after a bad station. Because you can pass a station despite a Borderline Fail judgement, finish strongly and move on.

Frequently Asked Questions

How many stations do you need to pass the CASC?

You need to pass at least 12 stations and also meet or exceed the total borderline regression score. Both conditions must be met.

Is the CASC marked as a percentage?

No. The pass mark is set by borderline regression for each exam day, so it is not a fixed percentage. It is calculated from how examiners marked candidates on the day, with a small standard error added.

Can you pass a station with a Borderline Fail?

Yes. The global judgement is used to set the pass mark, and a station is passed by reaching the station cut score. A Borderline Fail judgement does not automatically mean you failed that station.

What happens if you get two Severe Fail marks?

Two or more Severe Fail marks lead to a review of your overall performance by the Examinations Committee, and you may fail regardless of your total score or number of stations passed.

How long is each CASC station?

Each station has seven minutes for the task. Reading time is 4 minutes in the morning circuit and 90 seconds in the afternoon circuit.