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Burned out at your current job? Stuck in an occupation you never wanted? Are you looking for a change now that you've hit middle age but are afraid it's too late to shift careers? AARP, the advocacy group for older Americans, asked employment guru Dr. Laurence Shatkin, Ph.D. — the author of "The Sequel: How to Change Your Career Without Starting Over" — to pinpoint the best in-demand, high-growth jobs for people over age 40 who aren't afraid to "hit the books" again — whether that means entering a certificate program or "going all the way" and pursuing a master's degree. Here's a look at the six best jobs Shatkin recommends. Source: AARP

1. Industrial-organizational psychologist

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Average salary: $94,720 Industrial-organizational psychologists "apply research that improves the well-being and performance of people and the organizations that employ them," according to the Society for Industrial and Organizational Psychology. The group notes that duties range from employee selection and leader development to studying motivation and facilitating organizational change. You'll need a master's degree for this job yet older workers have a leg up on younger graduates. "Someone over 40 can use previous experience in the workplace to suggest topics for research, and provide insights that [more] green workers would not perceive," Shatkin told AARP. The job growth rate in this field is 35 percent, and industrial-organizational psychologists — unlike other psychology positions — do not need a doctorate.

2. Personal financial advisor

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Average salary: $66,580 This is an up-and-coming occupation with its own CNBC microsite: the Financial Advisor Hub at fa.cnbc.com. Shatkin says the projected growth rate for this occupation is 32 percent, and says it's a really good fit for people with experience or education in the finance or insurance fields. "Word of mouth is the main way advisors find clients, and seasoned workers who transition into this career benefit from having a better network for making such contacts," Shatkin told AARP. "The work can also be readily shifted to part-time, so easing gradually into retirement is an option." Degrees in economics, business or accounting also help, and studying to earn Certified Financial Planner status will go a long way in boosting credibility with potential clients. Licensing by a state regulatory board may also be required if you sell certain financial products, such as insurance policies.

3. Training and development specialist

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Average salary: $55,150 People persons with good communications skills should consider a career change to training and development specialist, a field with a projected 28 percent annual growth rate. According to AARP, these professionals "create, conduct and evaluate employee-training programs for corporations, financial institutions and government agencies." Shatkin told AARP that by teaching others, workers "can leverage knowledge of a field, but also build on people skills developed over a previous career." And many work arrangements are possible, from in-house to a self-employed trainer. A degree in human resources or business is usually a prerequisite for a training and development job, and government positions will also require a civil service exam. For a leg up on job opportunities, take the American Society of Training and Development's exam for Certified Professional in Learning and Performance Certification, says AARP.

4. Recreational therapist

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Average salary: $41,060 Recreational therapists get injured patients back on their feet using music and art, and games and sports. "You can utilize previous experience with a sport, art, dance or some other recreational activity — and the work demands compassion and interpersonal skills that older workers may have developed," Shatkin says. Normally, these positions require a bachelor's degree while having a master's will improve your hiring and pay prospects. Shatkin notes that employers in the field prefer certified therapists. Certification from the National Council for Therapeutic Recreation Certification requires passing a written exam and logging at least 480 hours as an intern. The organization awards recognition in seven specializations: adaptive sports and recreation, behavioral health, community inclusion services, developmental disabilities, geriatrics, pediatrics, and physical medicine/rehabilitation.

5. Medical records and health information technician

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Average salary: $33,310 Health care is America's largest and fastest-growing field — and therefore a perfect fit for over-40s looking for a new gig , according to Shatkin. Interpersonal and computer skills come in handy but "it's possible to work at many different levels of education and skill, and many jobs don't involve patient care," he told AARP. By next year, this field is expected to have grown by 21 percent. An associate's degree is usually required, along with professional certification as, for example, a Registered Health Information Technician (RHIT) or Certified Tumor Registrar (CTR).

6. Psychiatric technician

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