Our Team

Rebecca Jackson DO, CMD

Associate Chief Medical Officer

After receiving her undergraduate degree from Colorado State University, Dr. Jackson continued on to Kirksville College of Osteopathic Medicine. She then completed her residency at the Family Medicine Center in Fort Collins, followed by a fellowship in Geriatrics at Oregon Health Sciences University in Portland.

In the decade prior to joining NCH, Dr. Jackson focused on care of the elderly across a variety of settings including post-acute and long-term care. Her experience as a medical director spans entire systems of geriatric care including nursing home, assisted living, home health and therapy services. She has worked as a medical director for a provider group, focusing on policies to improve geriatric care and quality of life. She currently serves as a board member of the Colorado Medical Director Association. Her other professional areas of interest include dementia care, polypharmacy, and falls.

Outside of work she enjoys time with her family, hiking, riding her bike, or simply being in her garden.

Alaina Shilling CPC, CPB

PAC Practice and Revenue Cycle Manager

Alaina is a Fort Collins native who married her high school sweetheart and is now raising her two children in the Northern Colorado area. She graduated CSU in 2019 with a bachelor’s in healthcare business management with a specialization in Human Resources. She will graduate in 2025 with her master’s in business. Alaina is a certified coder and biller through AAPC and is a strong financial advocate for her patients. She also has three other clinical certifications to better understand the healthcare system. When she isn’t working or earning a new degree/certification, Alaina loves going to concerts and hockey games with her family (Go Avalanche!). She is an avid reader and loves animals. 

Katherine Knepper, MD, FACP

Dr. Knepper received her BA in Human Biology from Stanford University in 1993. She graduated from Northwestern University Medical School in 1999, and from their residency program in 2002. She spent eight years in private practice in Fort Collins before joining Northern Colorado Hospitalists. Her medical interests are in palliative care. Outside the hospital, she enjoys hiking, cooking, gardening, and spending time with her husband and son.

Amber McCollum, MD

I grew up in the Marshall Islands and went to medical school at the University of Hawaii, graduating in 2006. I trained in emergency medicine and worked in various ERs until 2017, when I started doing primary care and hospitalist work. Then in 2021 I got a geriatrics job and have found my calling. I love working with this population of people, many of whom have built Northern Colorado into the amazing place it is today. My husband works for CSU as a bison wildlife biologist. We have 2 girls and 2 dogs and we all love to play outside.

Karyn Leible, MD

Dr. Karyn Leible completed her nursing training in Boston many years ago and then went on to Boston University for an undergraduate degree in Biology. She moved to Colorado to work as a NICU nurse but became bored and went on to the University of Colorado to complete her medical education. She participated in an internal medicine residency and 2-year geriatric fellowship at the University of Colorado. She became involved with hospice and long-term care medicine during her fellowship. Dr. Leible has been actively involved in these areas providing care for the most vulnerable of our elders in these settings. She has held leadership positions in the national organization for post-acute and long-term medicine, AMDA- The Society for Past Acute and Long-Term Care Medicine. She lives in Fort Collins with her husband and a sassy moyen poodle.

Roger Birmingham, MD

Dr. Bermingham attended medical school at UCLA, followed by residency training in Family Medicine at the University of Iowa, becoming board certified in Family Medicine. After residency he practiced rural medicine in Lamar, Colorado, initially as part of the National Health Service Corps for 3 years then in private practice for another 4 years. In 1987 he moved to Fort Collins, CO to become faculty of the Family Medicine Residency at Poudre Valley Hospital and continued in that role until the end of 2022. He served as Residency Director from 1996 to 2001. Dr Bermingham became certified in Geriatrics in 1989, and his clinical practice gradually evolved into Geriatrics and Nursing Home Care. He is a Certified Medical Director through the Society for Post-Acute and Long-Term Care and for a 2-year period was faculty for that group’s training program for Nursing Home Medical Directors. He was honored to receive the Northern Colorado Medical Society’s Physician of the Year Award in 2015. Dr Bermingham and his high school sweetheart, Shelley, continue to make their home in Fort Collins. They have 3 children and 7 grandchildren.

Amy Mattox, MD

Dr. Mattox grew up in southern Arizona, moved to California for her undergraduate studies at Westmont College and medical school at Loma Linda University Medical School. Residency at North Colorado Family Medicine in Greeley brought her family to Colorado in 2007. For over a decade, she was a partner and primary care physician at Family Physicians of Greeley. She has also worked as family liaison in the COVID ICU and various traveling assignments. She is married with three daughters, and she and her husband own Boomer House in downtown Greeley. She enjoys painting, board games, glamping in Grover and driving her ‘71 Ford F250.

Kim Brown, RMA

Medical Assistant

Kim is a Wyoming native who moved to Colorado in 1998. She enjoys baking, gardening, tending to her plants and spending time with her husband and their dog. Kim has been a medical assistant for over 30 years and being able to help people is something that brings her great joy. 

Sarah Burton, NP

Nurse Practitioner

Sarah graduated from the University of Northern Colorado in 2020 from the NP program with geriatric and acute care focus. Prior to graduation, she had been a registered nurse for over a decade. Sarah’s experience as a nurse shaped her passion for caring for the geriatric population and since obtaining her NP, she has served the northern Colorado community in the long term and post-acute rehab setting. Outside of work, she loves spending time with her husband and their many rescue fur-babies. Sarah loves to hike, travel, tend to her garden and flowers, paint and create things, sports, and spending time with her extended family and friends.

Miranda Giglio, RMA

Medical Assistant

Miranda is a Kansas native who moved to Colorado in 2008. She has been in the medical field for over twenty years, with nine of those years being a Medical Assistant. She has always had a passion for helping individuals. Outside of work she loves spending time with her husband and their three children, at the softball field, gymnastics, crafting, or playing a good board game with everyone.

Elizabeth Longshore, NP

Nurse Practitioner

Liz completed her undergraduate education, graduating with a Bachelor of Science in Nursing (BSN) from the University of Cincinnati in 1995. After working as an ICU nurse for over 20 years, she completed her graduate degree in Adult Gerontology Nurse Practitioner in 2016. Since that time, Liz has enjoyed working with the adult population in various settings including independent and assisted living, long term care, and rehab and post-acute care. Her passion continues to guide each patient and family through life’s events, whether a short-term problem or a new chapter of change. During her time away from work, Liz enjoys gardening, hiking, and working on her backyard pond.

Kimberly Myers, NP

Nurse Practitioner

Kim grew up in Colorado, obtained nursing certification first in Sweden, then later updated nursing licensure through Pacific Lutheran University. She graduated from Frontier Nursing University with her Masters of Nursing with a focus on Family Practice in 2022. She has worked in Colorado in post-acute and long-term care settings. Kim enjoys spending time with family, running, traveling, and gardening. 

Sampson Ndikum, NP

Nurse Practitioner

Sampson Ndikum moved to the United States in 1993 from Cameroon. From there, he became a nurse’s aide, finding his passion in caring for people in need of help. He went on to become an LPN, RN, then BSN, and now FNP. He got his undergraduate degree from the University of Minnesota in Biochemistry and Pre Medicine. From there, he went to the University of Sint Eustatius School of Medicine and graduated in August 2009. Sampson then worked as a nurse for over twenty-four years before becoming an FNP, graduating from Western Governors University. He is looking forward to caring for and serving the patients of NCH. In his free time, he enjoys being out in nature, hiking with his wife and two birds, and golfing with his friends.  

Jessica Harper-Bischof, AGNP

As a former floor nurse at a skilled nursing facility, Jessi is very grateful to have the opportunity to guide care for older adults in the assisted living and skilled nursing setting. She loves the challenge of caring for people as they transition out of the hospital and make decisions about goals of care in order to assert their autonomy and make their lives as fulfilling as possible. Jessi received her BSN from the University of Northern Colorado and her MSN from American Sentinel College of Nursing and Health Sciences. In her first career, she was a Montessori teacher with a BA in English from Rice University and an MA in English/Rhetoric from the University of Houston. Outside of work, she loves reading, yoga, and spending time with her husband and children while gardening, paddle boarding, biking, rollerblading, camping, hiking, traveling, and otherwise being outdoors as much as possible.

Jennifer Bates, RMA

Post-Acute Care Medical Assistant

My name is Jennifer Bates, and I am so happy to be a part of NCH! A little about me: I am a Colorado Native and grew up in Arvada-where I still live. I have been in healthcare for over 20 years, and have worked within Orthopedics, Rheumatology, Family Medicine, and Dermatology. I have loved every modality, and on my journeys have been so very fortunate to have learned so much and made some wonderful life-long friends along the way. I feel grateful to have had so many wonderful experiences and am incredibly excited for my new journey with NCH! In my spare time, I greatly enjoy photography, golf, and fishing, as well as traveling along the gulf shores of Florida with my husband Troy as much as we are able. We have blended our family, and together share 5 beautiful children who we love spending time with and watching make their mark on the world. I am grateful for this wonderful opportunity and getting to know everyone!

Jordanna Peconi, MA

Post-Acute Care Medical Assistant

Born and raised in Colorado, Jordanna spent some time in Arizona while completing her AAS in medical administration. She and her hubby returned to Colorado to raise their family as she completed her Medical Assistant training. Jordanna enjoys spending time with her very active family. You will find her at the dirt racetrack, courtside at a basketball court, and coaching competitive girls fast pitch softball.

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