Table 5

 SPC variables*

*The variables are divided into eight categories and then further subdivided under subheadings in a category. Several articles reported more than one SPC variable.
I Biomedical variables
Blood glucose and HbA1c measures
1HbA1c level in groups of diabetic patients52
2Blood glucose, as a daily group average, for intensive care patients on parenteral or enteral nutrition33
3Average blood glucose levels among intensive care unit patients on total parenteral nutrition per week25
4Standard deviation of blood glucose levels among intensive care unit patients on total parenteral nutrition per week25
5Capillary blood glucose measurements of individual patients56
6Individual patient blood glucose measurements38
7Individual patient fasting blood sugar measurements37,50
8Average of five consecutive HbA1c measurements in diabetic patients cared for by one clinician50
Peak expiratory flow rates (PEFR)
9Daily am (ie, morning) pre-bronchodilator PEFR in asthmatic patients (litres/min)35,40
10Daily individual patient visual analogue pain scale recordings60
Cardiovascular system measures
11Blood pressure22,23,32
12Heart rate22,32
13Central venous pressure22
Urinary output
14Urinary output (during intensive care)22
Oxygen saturation
15Oxygen saturation (during intensive care)22
II Biomedical measurement variable
16Blood pressure measurement error (mm Hg)23
III Other variables related to patient health
17Patient fall rate (number of patient falls/number of cases per month)51
18Days in between asthma attacks70
19Nausea on day 3 after administration of chemotherapy, as reported by patients on a scale, displayed as the average in each sample of four consecutive patients67
20Incontinence volume (of fluid) for individual incontinent patients (in “a change-program”) on scheduled inspections16
21Volume of irrigation fluid absorbed during endoscopic renal pelvic surgery41
IV Clinical management variables
Time to complete (part of) a clinical process
22Time between patient check-in and interpretation of a preoperative radiograph17
23Door-to-needle time: “the time span between hospital admission and the initiation of thrombolytic therapy in patients with acute myocardial infarction”46,48
24Average length of stay for inpatients with congestive heart failure54
25Length of stay after cardiac surgery (risk adjusted and transformed)71
26Average length of stay for total hip replacement patients28
27Intensive care unit admission time42
28Average postoperative (bowel surgery) length of stay (in days) per month42
29Admission time (from “sign in” to “patient in room”)18,31
30Duration of intravenous antibiotic treatment for patients with pneumonia37
31Time to administration of antibiotic treatment for patients with pneumonia37
32Average length of hospital stay for inpatients with pneumonia37
33Time to extubation after coronary artery bypass grafting (CABG) surgery (hours)47
34Length of stay in the intensive care unit after CABG (days)47
35Total hospital length of stay after CABG (days)47
36Laboratory turnaround time for blood tests19,27
37Average postoperative length of stay after non-emergent CABG surgery, per quarter30
38Time from receiving a referral to first patient contact (days)49
Time, or number of consecutive cases, between events
39Time between deaths in chronic obstructive pulmonary disease54
40Number of successful elective CABG surgeries between cases with mortality42
41Number of successful CABG surgeries between cases with complications42
42Number of successful bowel resection operations between cases with complications42 (see also variable 18 for another example)
Rate of events in a clinical process (“defect rate” or “success rate”)
43Percentage of chief complaints (of patients in an emergency department) charted in free text (as opposed to coded) in the medical record, per day53
44Percentage of anaesthesia sessions with at least one “significant anaesthetic event”57
45Mortality in patients with congestive heart failure54
46Proportion of low birthweight infants54
47Percentage of intravenous medication administration events associated with an error24
48Occurrence of four intraoperative adverse events, of relevance to anaesthetic quality and safety: inadequate analgesia during brachial plexus block, emergence from general anaesthesia, intubation problems and medication errors64
49Proportion of patients with excessive absorption of irrigation fluid during transurethral resection of the prostate36
50Mortality after CABG42
51Proportion of patients on enteral, or parenteral, nutrition with blood glucose levels outside a (clinical management) target range33
52Daily percentage of satisfied requests for medical records at a paediatric outpatient clinic18
53“Guideline non-adherence rate”; proportion of chemotherapy administrations in which guideline recommendations to prevent nausea were not followed67
54Percentage of all blood cultures growing contaminants per month68
55Proportion of intensive care unit patients on total parenteral nutrition with blood glucose values that were higher than the given target (>11.1 mmol/l (>200 mg/dl)) per week25
56Percentage of all acute bronchitis visits during which a β-agonist was prescribed, per month34
57Percentage of all acute bronchitis visits during which an antibiotic was prescribed, per month34
58Percentage of outpatient surgical procedures per month (of all procedures)43
59Proportion of cases where tests were delayed or not reported in a timely fashion15
60Proportion of incontinent patients (in “a toileting program”) who were wet on scheduled inspections16
61Monthly percentage of emergency department patients who leave without being seen45
62Percentage of inpatients on the ward in each of three acuity levels (low, medium and high) per day26
63The quarterly incidence rate of eight variables among cardiac surgery patients: perioperative death, perioperative myocardial infarction; cerebrovascular accident; re-exploration for bleeding or tamponade; atrial fibrillation; leg wound; acute tubular necrosis; sternal infection; acute renal failure30
64Rates of total and major complications per patient after cardiac surgery30
65Proportion of first case starts each day in the operating theatres that are delayed due to the department of anaesthesia39
66Proportion of cases in which the turnaround time between cases exceeded the given performance standard39
Number of defects/events or occurrences in a clinical process
67Number of medication errors, per month24
68Number of out-of-hours “stat” (blood test analyses) requests received each week58
69Number of MRSA cases per month61
70Number of diabetes patients (seen at office visits) with HbA1c measurements, per month34
71Number of patients (seen at office visits) at a department of family medicine with a recorded diagnosis of tobacco abuse, per month34
72Total number of surgical procedures per month43
73Number of patients with diarrhoea admitted to the hospital, per week44
74Number of referrals per month for patients with diabetes from primary care to endocrinology55
75Number of new referrals per work day49
76Net number of new patients ( = practice growth)63
Clinical decision making
77(Square root of) the number of cases per general practitioner (GP) diagnosed as having tonsillitis versus number of cases diagnosed as having any throat infection62
78(Square root of) the number of GP patients diagnosed as having tonsillitis and non-tonsillar throat infection, who receive antibiotics62
79(Square root of) the number of GP cases with any throat infection diagnosis who received antibiotics62
80(Square root of) the number of GP cases with a diagnosis of sore throat in which antibiotics were not prescribed versus the number of cases in which antibiotics were prescribed66
V Financial resources variables
Cost of care
81Average cost per procedure (total hip replacement)28
82Staffing expense per shift, depicted as variance in US$ from budget26
83Staffing expense per 24-h period, depicted as variance in US$ from budget26
Productivity and efficiency
84Relative value unit (RVU) production per provider FTE (full-time equivalent) ( = provider productivity)63
85FTE support staff per FTE provider ( = practice efficiency)63
Organisational financial performance
86Net patient revenue per relative value unit (a primary care physician‘s practice) ( = practice profitability)63
87Provider cost as a percent of net revenue ( = practice cost management)63
88Non-provider cost as a percentage of net revenue ( = practice cost management)63
VI Variables relating to the experience of healthcare
Patient satisfaction indicators
89“Physician care scale score”, which is the average of patient survey responses to 10 questions59
90Patient satisfaction with (nursing) care65
91Percentage of patients (who responded to a patient satisfaction survey) whose response was that the overall visit was excellent29
Other experience with care
92Patient rating of assistance in solving the patient’s current health problem65
93Staff satisfaction with (nursing) care65
94Staff rating of assistance in solving patients’ current health problems65
VII Variables related to clinical staff supervision
Clinical staff supervision
95Active treatment monitoring index, based on observing staff performance in clinical encounters and assessing nine criteria20
Completion of mandatory staff training
96Percentage of employees who have completed mandatory safety training21
VIII Other variables
97“A temperature signal” (of unspecified origin; it is probably not body temperature since it varies around 74°F or 23°C). “[T]he signal could just as easily have been bed occupancy, ED wait time, expense per equivalent discharge, or staffed care days.”69