Procedure Volume Patient Data Patient Conditions Reviews Back to Top

Home > CA Providers > Emergency Physicians

Dr. Mary Ann H. Trephan, MD

(No ratings)

Specializes in: Emergency Medicine

18300 Roscoe Boulevard
Northridge, CA 91328

(818) 885-8500

Dr. Mary Ann H. Trephan, MD is an emergency medicine doctor in Northridge, CA specializing in emergency medicine.

Office Locations

18300 Roscoe Boulevard
Northridge, CA 91328

open_in_new

Noteworthy Medicare Patient Procedures Performed by Dr. Mary Ann H. Trephan, MD in 2023

Click on any procedure below to see further details on volume and pricing among Medicare patients.

Top 10%

By Volume:

lab tests

In 2023, Dr. Mary Ann H. Trephan, MD performed more lab tests procedures for Medicare patients than 90% of providers in related specialties within California.

Top 25%

By Volume:

rapid flu test

urinalysis

By Affordability:

influenza tests

rapid flu test

In 2012, among providers in related specialties within California, Dr. Mary Ann H. Trephan, MD performed more rapid flu test, and urinalysis procedures for Medicare patients than 75% of them and she also had a list price for influenza tests, and rapid flu test that was lower than the list prices billed to Medicare by 75% of them. Actual amounts paid by patients can vary widely depending on a number of factors, including insurance coverage. A lower list price, however, might mean lower fees when paying without insurance.

Medicare Procedure and Patient Information

2012 Medicare Procedure Volume

The top procedures that Dr. Mary Ann H. Trephan, MD treated as an emergency medicine doctor in Northridge, CA during 2012 were emergency care, X-rays and thoracic (chest) imaging.

Volume of procedures performed by Dr. Mary Ann H. Trephan, MD for Medicare patients.

emergency care	208
thoracic (chest) imaging	40
X-rays	40

Medicare Procedure and Patient Information

2013 Medicare Procedure Volume

The top procedures that Dr. Mary Ann H. Trephan, MD treated as an emergency medicine doctor in Northridge, CA during 2013 were emergency care, X-rays and thoracic (chest) imaging.

Volume of procedures performed by Dr. Mary Ann H. Trephan, MD for Medicare patients.

emergency care	240
thoracic (chest) imaging	56
X-rays	56

2013 Medicare Patient Data

Information about Medicare patients treated by Dr. Mary Ann H. Trephan, MD.

**Gender**
Male	117
Female	151

**Ethnicity**
Non-Hispanic White	163
Black	0
Hispanic	58
Asian	27
Other	0
Native American	0

**Age**
From 65 to 74	70
From 75 to 84	73
85 and over	68
Less than 65	57

Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD in 2013

Hypertension	75
High Cholesterol	63
Stroke	15
Ischemic Heart Disease	60
Depression	43
Chronic Kidney Disease	50
Asthma	14
Osteoperosis	15
Atrial Fibrilation	19
Heart Failure	42
Chronic Obstructive Pulmonary Disease	26
Diabetes	43
Dementia	32
Cancer	11

Medicare Procedure and Patient Information

2014 Medicare Procedure Volume

The top procedures that Dr. Mary Ann H. Trephan, MD treated as an emergency medicine doctor in Northridge, CA during 2014 were emergency care, X-rays and thoracic (chest) imaging.

Volume of procedures performed by Dr. Mary Ann H. Trephan, MD for Medicare patients.

emergency care	225
thoracic (chest) imaging	97
X-rays	97

2014 Medicare Patient Data

Information about Medicare patients treated by Dr. Mary Ann H. Trephan, MD.

**Gender**
Male	111
Female	148

**Ethnicity**
Non-Hispanic White	154
Black	0
Hispanic	57
Asian	26
Other	0
Native American	0

**Age**
From 65 to 74	61
From 75 to 84	72
85 and over	72
Less than 65	54

Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD in 2014

Hypertension	75
High Cholesterol	66
Stroke	15
Ischemic Heart Disease	62
Depression	42
Chronic Kidney Disease	57
Asthma	17
Osteoperosis	18
Atrial Fibrilation	22
Heart Failure	51
Chronic Obstructive Pulmonary Disease	31
Diabetes	51
Dementia	34
Cancer	17

Medicare Procedure and Patient Information

2015 Medicare Procedure Volume

The top procedures that Dr. Mary Ann H. Trephan, MD treated as an emergency medicine doctor in Northridge, CA during 2015 were emergency care, X-rays and thoracic (chest) imaging.

Volume of procedures performed by Dr. Mary Ann H. Trephan, MD for Medicare patients.

emergency care	304
thoracic (chest) imaging	28
X-rays	28

2015 Medicare Patient Data

Information about Medicare patients treated by Dr. Mary Ann H. Trephan, MD.

**Gender**
Male	270
Female	346

**Ethnicity**
Non-Hispanic White	380
Black	32
Hispanic	110
Asian	62
Other	32
Native American	0

**Age**
From 65 to 74	154
From 75 to 84	158
85 and over	158
Less than 65	146

Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD in 2015

Hypertension	75
High Cholesterol	64
Stroke	9
Ischemic Heart Disease	66
Depression	45
Chronic Kidney Disease	53
Asthma	23
Osteoperosis	16
Atrial Fibrilation	17
Heart Failure	50
Chronic Obstructive Pulmonary Disease	30
Diabetes	48
Dementia	30
Cancer	10

Medicare Procedure and Patient Information

2016 Medicare Procedure Volume

The top procedures that Dr. Mary Ann H. Trephan, MD treated as an emergency medicine doctor in Northridge, CA during 2016 were emergency care.

Volume of procedures performed by Dr. Mary Ann H. Trephan, MD for Medicare patients.

emergency care	259

2016 Medicare Patient Data

Information about Medicare patients treated by Dr. Mary Ann H. Trephan, MD.

**Gender**
Male	121
Female	166

**Ethnicity**
Non-Hispanic White	164
Black	13
Hispanic	67
Asian	30
Other	0
Native American	0

**Age**
From 65 to 74	73
From 75 to 84	75
85 and over	75
Less than 65	64

Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD in 2016

Hypertension	75
High Cholesterol	66
Stroke	16
Ischemic Heart Disease	63
Depression	45
Chronic Kidney Disease	57
Asthma	35
Osteoperosis	21
Atrial Fibrilation	22
Heart Failure	55
Chronic Obstructive Pulmonary Disease	32
Diabetes	51
Dementia	30
Cancer	10

Medicare Procedure and Patient Information

2017 Medicare Procedure Volume

The top procedures that Dr. Mary Ann H. Trephan, MD treated as an emergency medicine doctor in Northridge, CA during 2017 were emergency care.

Volume of procedures performed by Dr. Mary Ann H. Trephan, MD for Medicare patients.

emergency care	251

2017 Medicare Patient Data

Information about Medicare patients treated by Dr. Mary Ann H. Trephan, MD.

**Gender**
Male	118
Female	143

**Ethnicity**
Non-Hispanic White	151
Black	14
Hispanic	45
Asian	39
Other	12
Native American	0

**Age**
From 65 to 74	61
From 75 to 84	69
85 and over	81
Less than 65	50

Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD in 2017

Hypertension	75
High Cholesterol	64
Stroke	16
Ischemic Heart Disease	67
Depression	43
Chronic Kidney Disease	62
Asthma	14
Osteoperosis	17
Atrial Fibrilation	26
Heart Failure	54
Chronic Obstructive Pulmonary Disease	33
Diabetes	54
Dementia	38
Cancer	13

Medicare Procedure and Patient Information

2018 Medicare Procedure Volume

The top procedures that Dr. Mary Ann H. Trephan, MD treated as an emergency medicine doctor in Northridge, CA during 2018 were emergency care.

Volume of procedures performed by Dr. Mary Ann H. Trephan, MD for Medicare patients.

emergency care	232

2018 Medicare Patient Data

Information about Medicare patients treated by Dr. Mary Ann H. Trephan, MD.

**Gender**
Male	123
Female	140

**Ethnicity**
Non-Hispanic White	155
Black	0
Hispanic	52
Asian	37
Other	0
Native American	0

**Age**
From 65 to 74	73
From 75 to 84	77
85 and over	71
Less than 65	42

Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD in 2018

Hypertension	75
High Cholesterol	72
Stroke	15
Ischemic Heart Disease	68
Depression	42
Chronic Kidney Disease	60
Asthma	16
Osteoperosis	15
Atrial Fibrilation	22
Heart Failure	51
Chronic Obstructive Pulmonary Disease	23
Diabetes	49
Dementia	43
Cancer	14

Medicare Procedure and Patient Information

2019 Medicare Procedure Volume

The top procedures that Dr. Mary Ann H. Trephan, MD treated as an emergency medicine doctor in Northridge, CA during 2019 were emergency care.

Volume of procedures performed by Dr. Mary Ann H. Trephan, MD for Medicare patients.

emergency care	195

2019 Medicare Patient Data

Information about Medicare patients treated by Dr. Mary Ann H. Trephan, MD.

**Gender**
Male	106
Female	129

**Ethnicity**
Non-Hispanic White	134
Black	0
Hispanic	45
Asian	33
Other	0
Native American	0

**Age**
From 65 to 74	72
From 75 to 84	66
85 and over	60
Less than 65	37

Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD in 2019

Hypertension	75
High Cholesterol	72
Stroke	15
Ischemic Heart Disease	74
Depression	44
Chronic Kidney Disease	66
Asthma	14
Osteoperosis	19
Atrial Fibrilation	0
Heart Failure	57
Chronic Obstructive Pulmonary Disease	29
Diabetes	63
Dementia	36
Cancer	17

Medicare Procedure and Patient Information

2020 Medicare Procedure Volume

The top procedures that Dr. Mary Ann H. Trephan, MD treated as an emergency medicine doctor in Northridge, CA during 2020 were emergency care.

Volume of procedures performed by Dr. Mary Ann H. Trephan, MD for Medicare patients.

doctor visit	67
emergency care	131

2020 Medicare Patient Data

Information about Medicare patients treated by Dr. Mary Ann H. Trephan, MD.

**Gender**
Male	106
Female	127

**Ethnicity**
Non-Hispanic White	161
Black	0
Hispanic	30
Asian	15
Other	13
Native American	0

**Age**
From 65 to 74	89
From 75 to 84	73
85 and over	42
Less than 65	29

Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD in 2020

Hypertension	75
High Cholesterol	70
Stroke	9
Ischemic Heart Disease	55
Depression	40
Chronic Kidney Disease	42
Asthma	9
Osteoperosis	15
Atrial Fibrilation	16
Heart Failure	34
Chronic Obstructive Pulmonary Disease	16
Diabetes	41
Dementia	24
Cancer	9

Medicare Procedure and Patient Information

2021 Medicare Procedure Volume

The top procedures that Dr. Mary Ann H. Trephan, MD treated as an emergency medicine doctor in Northridge, CA during 2021 were emergency care.

Volume of procedures performed by Dr. Mary Ann H. Trephan, MD for Medicare patients.

doctor visit	130
emergency care	11

2021 Medicare Patient Data

Information about Medicare patients treated by Dr. Mary Ann H. Trephan, MD.

**Gender**
Male	60
Female	88

**Ethnicity**
Non-Hispanic White	126
Black	0
Hispanic	0
Asian	0
Other	0
Native American	0

**Age**
From 65 to 74	71
From 75 to 84	43
85 and over	17
Less than 65	17

Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD in 2021

Hypertension	58
High Cholesterol	65
Stroke	0
Ischemic Heart Disease	40
Depression	28
Chronic Kidney Disease	28
Asthma	15
Osteoperosis	17
Atrial Fibrilation	14
Heart Failure	18
Chronic Obstructive Pulmonary Disease	11
Diabetes	23
Dementia	13
Cancer	14

Medicare Procedure and Patient Information

2022 Medicare Procedure Volume

The top procedures that Dr. Mary Ann H. Trephan, MD treated as an emergency medicine doctor in Northridge, CA during 2022 were lab tests and blood draw.

Volume of procedures performed by Dr. Mary Ann H. Trephan, MD for Medicare patients.

blood draw	23
doctor visit	235
lab tests	108

2022 Medicare Patient Data

Information about Medicare patients treated by Dr. Mary Ann H. Trephan, MD.

**Gender**
Male	83
Female	163

**Ethnicity**
Non-Hispanic White	205
Black	0
Hispanic	12
Asian	0
Other	14
Native American	0

**Age**
From 65 to 74	127
From 75 to 84	79
85 and over	26
Less than 65	14

Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD in 2022

Hypertension	60
High Cholesterol	70
Stroke	12
Ischemic Heart Disease	26
Depression	21
Chronic Kidney Disease	18
Asthma	13
Osteoperosis	22
Atrial Fibrilation	17
Heart Failure	9
Chronic Obstructive Pulmonary Disease	13
Diabetes	25
Dementia	4
Cancer	17

Medicare Procedure and Patient Information

2023 Medicare Procedure Volume

The top procedures that Dr. Mary Ann H. Trephan, MD treated as an emergency medicine doctor in Northridge, CA during 2023 were lab tests and blood draw.

Volume of procedures performed by Dr. Mary Ann H. Trephan, MD for Medicare patients.

blood draw	29
doctor visit	453
lab tests	208

2023 Medicare Patient Data

Information about Medicare patients treated by Dr. Mary Ann H. Trephan, MD.

**Gender**
Male	163
Female	265

**Ethnicity**
Non-Hispanic White	373
Black	0
Hispanic	16
Asian	0
Other	21
Native American	0

**Age**
From 65 to 74	192
From 75 to 84	173
85 and over	52
Less than 65	11

Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD in 2023

Hypertension	69
High Cholesterol	75
Stroke	7
Ischemic Heart Disease	29
Depression	20
Chronic Kidney Disease	19
Asthma	14
Osteoperosis	22
Atrial Fibrilation	17
Heart Failure	12
Chronic Obstructive Pulmonary Disease	12
Diabetes	22
Dementia	5
Cancer	18

Medicare Procedure and Patient Information

Average Medicare Procedure Volume From 2012 - 2023

Volume of procedures performed by Dr. Mary Ann H. Trephan, MD for Medicare patients.

The highest averages for the top procedures that Dr. Mary Ann H. Trephan, MD treated as an emergency medicine doctor in Northridge, CA were emergency care, lab tests, X-rays and thoracic (chest) imaging.

blood draw	26
doctor visit	221
emergency care	205
lab tests	158
thoracic (chest) imaging	55
X-rays	55

Average Medicare Patient Data From 2012 - 2023

Information about Medicare patients treated by Dr. Mary Ann H. Trephan, MD.

**Gender**
Female	155
Male	114

**Ethnicity**
Black / African American	4
Asian / Pacific Islander	22
Non-Hispanic White	180
Native American / Alaskan Native	0
Hispanic	41
Other	7

**Age**
85 and over	60
75 to 84	79
Less than 65	43
65 to 74	86

Average of Total of Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD From 2012 - 2023

The highest averages of the most common conditions of Medicare patients that Dr. Mary Ann H. Trephan, MD treated were hypertension, high cholesterol, ischemic heart disease and chronic kidney disease.

Hypertension	65
High Cholesterol	62
Stroke	10
Ischemic Heart Disease	50
Depression	34
Chronic Kidney Disease	42
Asthma	15
Osteoporosis	16
Heart Failure	36
Chronic Obstructive Pulmonary Disease	21
Diabetes	39
Atrial Fibrillation	16
Dementia	24
Cancer	12

Education & Training

She has a state license in California.

Licensed In: California

Ratings & Reviews

Dr. Mary Ann H. Trephan, MD does not have any reviews yet, be the first to leave a review of Dr. Mary Ann H. Trephan, MD here: Leave a Review

(No ratings)

Leave a Review

Biography

Dr. Mary Ann Trephan is a specialist in emergency medicine. Dr. Trephan is professionally affiliated with Southern California Permanente Medical Group (SCPMG). She studied medicine at Thomas Jefferson University, Jefferson Medical College.

Select Year:

Dr. Mary Ann H. Trephan, MD

Office Locations

Noteworthy Medicare Patient Procedures Performed by Dr. Mary Ann H. Trephan, MD in 2023

By Volume:

By Volume:

By Affordability:

Medicare Procedure and Patient Information

2012 Medicare Procedure Volume

Medicare Procedure and Patient Information

2013 Medicare Procedure Volume

2013 Medicare Patient Data

Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD in 2013

Medicare Procedure and Patient Information

2014 Medicare Procedure Volume

2014 Medicare Patient Data

Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD in 2014

Medicare Procedure and Patient Information

2015 Medicare Procedure Volume

2015 Medicare Patient Data

Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD in 2015

Medicare Procedure and Patient Information

2016 Medicare Procedure Volume

2016 Medicare Patient Data

Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD in 2016

Medicare Procedure and Patient Information

2017 Medicare Procedure Volume

2017 Medicare Patient Data

Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD in 2017

Medicare Procedure and Patient Information

2018 Medicare Procedure Volume

2018 Medicare Patient Data

Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD in 2018

Medicare Procedure and Patient Information

2019 Medicare Procedure Volume

2019 Medicare Patient Data

Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD in 2019

Medicare Procedure and Patient Information

2020 Medicare Procedure Volume

2020 Medicare Patient Data

Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD in 2020

Medicare Procedure and Patient Information

2021 Medicare Procedure Volume

2021 Medicare Patient Data

Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD in 2021

Medicare Procedure and Patient Information

2022 Medicare Procedure Volume

2022 Medicare Patient Data

Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD in 2022

Medicare Procedure and Patient Information

2023 Medicare Procedure Volume

2023 Medicare Patient Data

Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD in 2023

Medicare Procedure and Patient Information

Average Medicare Procedure Volume From 2012 - 2023

Average Medicare Patient Data From 2012 - 2023

Average of Total of Conditions of Medicare patients treated by Dr. Mary Ann H. Trephan, MD From 2012 - 2023

Education & Training

Ratings & Reviews

Biography

Other Providers in Northridge, CA