Here are some tips:

1) Start with a short 1 sentence intro.

2) Get right to the point quickly in a clear and easy to understand way. Eliminate all long winded and/or confusing language.

3) Most people will be very wary of clicking links in a cold-call email. Partially because it would take time, and partially because of scam wariness. To get around that negative bias, include a professional looking screenshot of your SaaS and anything else that would convince them that you're legit and that they'd want to use it (1-2 screenshots, 1-3 main features, 1-3 positive reviews, logos of any online news/blog coverage). Have all of this be in-line, not as attachments.

To facilitate their demo call booking, use YouCanBookMe (https://youcanbook.me/). They'll see a simple calendar with times they can book for a demo, without any need to email or call you back to set up a time.

4) If allowed in this project, look into other routes other than emails. For instance:

A) Post it to relevant subreddits (https://www.reddit.com/r/doctors/, etc.).

B) If possible, mail a small gift (e.g. a small chocolate) to your potential leads, and have a note on the chocolate with an intro and a link (use an URL shortener) and/or QR code. Even if they don't go to the link on the note, you could do a follow up email in which you mention that you previously sent them the gift, which will increase your success.

If you'd like to discuss other techniques more tailored to your specific product let me know,

best,

Lee