I had never heard of it, but I just looked it up and it says:
Q. What are the 16 specialties the MSPI includes?
A. Many of the specialties that you can enter during the first two years of residency training are included:
- Anesthesiology
- Dermatology
- Emergency Medicine
- Family Medicine
- Internal Medicine
- Neurology
- Obstetrics and Gynecology
- Orthopaedic Surgery
- Otolaryngology
- Pathology –Anatomic and Clinical
- Pediatrics
- Physical Medicine and Rehabilitation
- Psychiatry
- Radiology –Diagnostic
- Surgery –General
- Urology
So there are a lot of specialties that are not included.
If you're just starting 2nd year you're still missing the whole in-person experience. Maybe once you've had some experience in inpatient vs. outpatient settings, gotten a feel for the the OR, ICU, clinic, etc., you'll be able to contextualize the recommendations a little better. A lot of specialties are not at all like what premeds or M1-M2s (or even practicing physicians in another specialty) understand them to be.
They could also be totally inaccurate for you. It would be a mistake to trust these results over your own feelings, especially once you start spending time on those services. The only reason I can see to heed these recommendations are to consider something new that you hadn't thought of before, or to feel more confident in your choice if your own interests align with their results.