You have been hired as an intern by a Community Hospital. Your first task is to develop an E- R diagram for the hospital. You have conducted interviews with a number of hospital administrators and staff to identify the key entity types for the hospital. You have identified the following entity types:

Care Centera treatment center within the hospital. Examples of care centers are maternity, emergency care, or multiple sclerosis center. Each care center has a care center ID (identifier) and a care center name.

Patienta person who is either admitted to the hospital or is registered as an outpatient. Each patient has an identifier, the medical record number (MRN), and a name.

Physiciana member of the hospital medical staff who may admit patients to the hospital and who may administer medical treatments. Each physician has a physician ID (identifier) and name.

Beda hospital bed that may be assigned to a patient who is admitted to the hospital. Each bed has a bed number, a room number, and a care center ID.

Itemany medical or surgical item that may be used in treating a patient. Each item has an item number, description, and unit cost.

Employeeany person employed as part of the hospital staff. Each employee has an employee number and name.

Diagnosisa patients medical condition diagnosed by a physician. Each diagnosis has a diagnosis code and diagnosis name.

Treatmentany test or procedure ordered by and/or performed by a physician for a patient. Each treatment has a treatment code and treatment name.

Orderany order issued by a physician for treatment and/or services such as diagnostic tests (radiology, laboratory) and therapeutic procedures (physical therapy, diet orders), or drugs and devices (prescriptions). Each order has an order ID, order date, and order time.

You next recorded the following information concerning relationships:

Each hospital employee is assigned to work in one or more care centers. Each care center has at least one employee and may have any number of employees. The hospital records the number of hours per week that a given employee works in a particular care center.

Each care center has exactly one employee who is designated nurse-in-charge for that care center.

A given patient may or may not be assigned to a bed (since some patients are outpatients). Occupancy rates are seldom at 100 percent, so a bed may or may not be assigned to a patient.

A patient may be referred to the hospital by exactly one physician. A physician may refer any number of patients or may not refer any patients.

A patient must be admitted to the hospital by exactly one physician. A physician may admit any number of patients or may not admit any patients.

Prior to a patient being seen by a physician, a nurse typically obtains and records relevant information about the patient. This includes the patients weight, blood pressure, pulse, and temperature. The nurse who assesses the vital signs also records the date and time. Finally, the reasons for the visit and any symptoms the patient describes are recorded.

Physicians diagnose any number of conditions affecting a patient, and a diagnosis may apply to many patients. The hospital records the following information: date and time of diagnosis, diagnosis code, and description.

Physicians may order and perform any number of services/treatments for a patient or may not perform any treatment. A treatment or service may be performed on any number of patients, and a patient may have treatments performed or ordered by any number of physicians. For each treatment or service rendered, the hospital records the following information: physician ordering the treatment, treatment date, treatment time, and results.

A patient may also consume any number of items. A given item may be consumed by one or more patients, or may not be consumed. For each item consumed by a patient, the hospital records the following: date, time, quantity, and total cost (which can be computed by multiplying quantity times unit cost).