Mastering Case Formulation: Key Mistakes and Improvements for Psychologists
- Amanda Moses Psychology
- Apr 21
- 4 min read
Updated: May 6
Case formulation is one of the most powerful tools we have as psychologists. A strong formulation helps us understand our client’s distress, guide our interventions, and make sense of what’s working—and what isn’t. However, it’s also something that many early-career psychologists struggle with.
Over the years, I’ve supervised dozens of provisionals. The same issues come up time and again. So, let’s talk about some common case formulation mistakes I see—and more importantly, how to fix them.
1. Jumping to Diagnosis Without Understanding the Problem
One of the biggest mistakes is prematurely anchoring to a diagnosis. This often happens without fully understanding what’s actually happening for the client.
Let’s consider a scenario where a client presents with low mood, fatigue, and loss of interest in activities. It’s tempting to jump straight to “depression.” However, what if the low mood is due to burnout? Or grief? Or even a medical condition? Without a proper formulation, we risk addressing the wrong issue.
💡 Fix it: Focus on what’s driving the distress—not just the symptoms. Ask critical questions: What sustains this pattern? When did the symptoms begin? What reinforces it? What role do these behaviors or feelings play functionally?
2. Missing the Precipitating and Predisposing Factors
Another common error is missing the predisposing and precipitating factors in a case formulation. Too often, I see formulations that focus only on “here and now” issues. This narrow focus can result in a superficial understanding of the client’s context and missed therapeutic opportunities.
💡 Fix it: Always use the 5Ps (Predisposing, Presenting, Precipitating, Perpetuating, and Protective factors). These factors are not just for Cognitive Behavioral Therapy (CBT); they are valuable in any therapeutic model. Examine early developmental experiences, family dynamics, critical incidents, and systemic factors. Understanding what led to the problem is just as crucial as recognizing what keeps it going.
3. Overlooking Reinforcement Cycles
One of the most teachable moments in case formulation is the oversight of reinforcement cycles. For instance, a client with social anxiety may avoid social events, leading to temporary distress reduction. This relief becomes reinforcing, making the avoidance more likely to continue, even if it worsens the long-term problem.
💡 Fix it: Identify any short-term rewards that maintain the problem. These can be subtle, including avoidance, reassurance-seeking, or people-pleasing behaviors. Once you recognize this pattern, you can devise interventions to gently interrupt it.
4. Treating the Symptom, Not the System
Some formulations malfunction when they focus solely on visible symptoms. They ignore the broader systems in which the client operates. For example, concentrating solely on a young person’s depressive symptoms without exploring family dynamics, trauma history, neurodivergence, or peer relationships leaves critical gaps in understanding.
💡 Fix it: Adopt a systemic view. Consider how relationships, culture, neurobiology, trauma, or environmental stressors play a role. Treating isolated symptoms rarely leads to long-lasting change.
5. Overcomplicating It (Or Oversimplifying It)
The final trap in case formulation is either making formulations too abstract to be actionable or oversimplifying them to the point they offer little clinical guidance. Often, formulations consist of vague jargon or, conversely, a one-sentence summary.
💡 Fix it: Craft formulations as working theories. They should be detailed enough to guide interventions but flexible enough to evolve. I recommend using clear headings (e.g., presenting issue, maintaining factors, strengths, treatment implications) and updating them as therapy progresses.
The Importance of Collaboration
Collaboration with clients can also enhance the case formulation process. Clients often have valuable insights regarding their experiences. Allowing them to engage in the formulation discussion fosters a sense of ownership over the treatment plan. This approach can lead to better outcomes, as clients are more likely to follow through when they feel heard and involved.
Case Formulation Is a Skill—And You Can Get Better at It
Case formulation is not just for CBT. It is a foundational skill that applies across therapeutic modalities. It aids in avoiding assumptions, reducing reactivity, and working in a thoughtful, tailored, and ethically sound manner.
Remember, a case formulation is not just an opinion—it’s a clinically-driven hypothesis. It should be grounded in psychological theory, aligned with the evidence base, and shaped by the information gathered during assessment.
For example, if you hypothesize that a client’s perfectionism is maintained by early attachment experiences and reinforced by current performance-based validation at work, that’s not a random guess. It is a working theory based on established patterns in schema theory, developmental psychology, and behavioral models. It is something you will test, refine, and adjust as therapy progresses.
💡 A good formulation is clear, collaborative, and evidence-informed. It isn’t static; it evolves as the client grows, new information emerges, or treatment needs change.
Want Support with Case Formulation?
If you would like support in developing stronger, more structured formulations, I’ve got you covered:
🧠 My Therapy Manual Bundle includes clear examples, editable formulation templates, and real-world illustrations you can incorporate into your practice.
🎓 My Case Formulation & Treatment Planning Clinical Resource breaks down formulation step-by-step. It includes a customizable and editable template—perfect for early-career psychologists or anyone looking to refresh their skills.
✔ Let’s stop guessing and start formulating with purpose.
