Study reference

Study characteristics

Patient characteristics

Index test

(test of interest)

Reference test

Follow-up

Outcome measures and effect size

Comments

Almajid, 2019

Type of study: retrospective study

Setting and country: hospital, Saudi Arabia

Funding and conflicts of interest: no conflict of interest

Inclusion criteria:

All patients with PSP who underwent

chest CT evaluation during their admission (January 2005- December 2015)

Exclusion criteria: no chest evaluation

N=143

Of which 23 patients underwent only a drainage procedure

Mean age ± SD: 24 ± 6.2

Sex: % M / % F: 141/2

Other important characteristics:

Pneumothorax side:

right/left: 70/73

ipsilateral/contraolateral:

blebs: 119/103

contralateral: 32/21

Describe index test: The chest CT in this study was a highresolution

non-contrast-enhanced CT of the chest with 64-row MDCT (SOMATOM Definition, Siemens Healthcare Sector; Forchheim, Germany) using a standardized

chest CT protocol with the following parameters: collimation:

32 × 2 × 0.6 mm; weight-adapted selection of the tube voltage for both tubes (ranging between 100 and 120 kV) with adapted tube current setting (ranging between 90 and 100 effective mAs); 4D dose modulation (Care Dose 4D); pitch: 3; rotation time: 0.28 s. The scan range was from the level of the pulmonary apex to the costophrenic angle. All patients underwent CT scan examinations in the supine position and were required to hold their breath at

full inspiration. CT images of 1-mm slice thickness for 2-mm intervals

in the lung parenchyma in axial and coronal (window level: − 600 HU; window width: 1500 HU) were used for analysis.

All chest CT

examinations of the patients were reviewed by one expert

radiologist looking for the presence of ipsilateral and contralateral

blebs or bullae and the presence of other abnormalities

in the lung or pleura.

Describe reference test:

The surgical management includes intercostal chest tube

drainage of the pneumothorax that may be followed by

surgical exploration of the pleural cavity depending on

the patient response to the drainage procedure.

The surgical exploration

was carried out mostly by video-assisted thoracoscopic surgery looking for pulmonary blebs or bullae for resection with or without the use of pleurodesis.

CT scan was performed before surgery

Outcome measures and effect size (include 95%CI and p-value if available):

Sensitivity: 95.7%

Specificity: 42.3%

The calculated positive and negative predictive

values for the chest CT scan were 85.7% and 73.3%,

respectively

Kawaguchi, 2013

Type of study: retrospective study

Setting and country: Hospital, Japan

Funding and conflicts of interest: no conflict of interest

Inclusion criteria: patients who underwent surgery from

September 2005 to October 2009. Indications were prolonged airleak or repeated pneumothorax.

Exclusion criteria: Patients with secondary pneumothorax or recurrent PSP were excluded from this analysis. PSP patients who did not undergo preoperative chest CT were also excluded.

N= 93

Mean age ± SD: 32 ± 16

Sex: % M / % F: 74/19

Other important characteristics:

Size PSP by chest radiograph:

Small n=24

Moderate n=25

Complete n=44

Recurrence PSP

Yes n=7

No n=86

Describe index test:

Preoperative chest radiographic and CT imaged were retrospectively reviewed. No details regarding the CT scan was presented.

Describe reference test:

All patients were treated using video-assisted thoraco-

Scopic surgery (VATS) under general anesthesia with single-lung ventilation. They used three ports VATS.

CT scan was performed before surgery

Outcome measures and effect size (include 95%CI and p-value if available):

Sensitivity: 84%

Specificity: 100%

Lee, 2014

Type of study:

Retrospective cohort

Setting and country: Hospital, Korea

Funding and conflicts of interest: no conflict of interest

Inclusion criteria: From January 2010 to January 2013, 31 patients with

preoperative CT scans who underwent wedge resection of

BBs for PSP in our hospital were retrospectively reviewed

for this study.

Exclusion criteria:

N=33

Mean age ± SD: 20 ± 5 years (range, 10–37 years).

Sex: % M / % F: 28/3

Other important characteristics: unknown

The parameters used in chest CT examinations

(Siemens Sensation 64, Siemens Medical Solutions,

Erlangen, Germany) were as follows: 100–120 kVp,

170 mAs, 0.6-mm collimation, 10-mm/s table feed and

1-s rotation time using routine reconstruction algorithms

of a 5-mm slice thickness and 5-mm slice interval. Synthetic

high-resolution CT (HRCT) images were also

reconstructed using a 1-mm slice thickness

Wedge resection for blebs and bullae

CT scan was performed before surgery

Outcome measures and effect size (include 95%CI and p-value if available):

Sensitivity:

HRCT: 97,0%

Routin CT: 63,6%

Sihoe, 2000

Type of study:

Prospective study

Setting and country: Hospital, China

Funding and conflicts of interest: Not described

Inclusion criteria: Between May 1994 and March 1995, 31 consecutive patients

who presented with unilateral PSP and planned to undergo

ipsilateral VATS as definitive treatment were recruited for this

study. Indications for surgery were recurrent PSP (n 5 17),

tension pneumothorax at first presentation (n 5 6), persistent air

leak (n 5 6), or patient occupation (eg, flight crew) (n 5 2).

Exclusion criteria: Two patients declined to participate in the study, and one other patient defaulted on follow-up; therefore, they were excluded from the final analysis.

N= 28

Mean age (range): 29 (18-47)

Sex: % M / % F: 23/5

Other important characteristics:

high-resolution CT scan of the thorax was performed on each patient. Plain CT scans (lung windows only) were performed using a spiral CT scanner (model B7999RP-CT HiSpeed Advantage RP Scanner; GE Medical Systems; Milwaukee, WI). A slice thickness of 1 mm and a section spacing of 10

mm were selected.

By convention, blebs are defined by

the radiologist to be small air collections, 1 cm in diameter, as

opposed to bullae, which are. 1 cm in diameter.

Unilateral VATS

A thorough exploration was performed to detect the presence of apical

lung blebs or bullae (ruptured or intact).

CT scan was performed before surgery

Outcome measures and effect size (include 95%CI and p-value if available):

Sensitivity: 88%

Study reference

Patient selection

Index test

Reference standard

Flow and timing

Comments with respect to applicability

Almajid, 2019

Was a consecutive or random sample of patients enrolled?

Yes

Was a case-control design avoided?

Yes

Did the study avoid inappropriate exclusions?

Yes

Were the index test results interpreted without knowledge of the results of the reference standard?

Yes

If a threshold was used, was it pre-specified?

Yes

Is the reference standard likely to correctly classify the target condition?

Yes

Were the reference standard results interpreted without knowledge of the results of the index test?

Unclear, but likely that the surgeon reviewed the CT scan prior to the procedure.

Was there an appropriate interval between index test(s) and reference standard?

Yes

Did all patients receive a reference standard?

No, 23 patients underwent drainage

Did patients receive the same reference standard?

No (“mostly VATS”)

Were all patients included in the analysis?

Yes

Are there concerns that the included patients do not match the review question?

No

Are there concerns that the index test, its conduct, or interpretation differ from the review question?

No

Are there concerns that the target condition as defined by the reference standard does not match the review question?

No

CONCLUSION:

Could the selection of patients have introduced bias?

RISK: LOW

CONCLUSION:

Could the conduct or interpretation of the index test have introduced bias?

RISK: LOW

CONCLUSION:

Could the reference standard, its conduct, or its interpretation have introduced bias?

RISK: HIGH

CONCLUSION

Could the patient flow have introduced bias?

RISK: LOW

Kawaguchi, 2013

Was a consecutive or random sample of patients enrolled?

Yes

Was a case-control design avoided?

Yes

Did the study avoid inappropriate exclusions?

Yes

Were the index test results interpreted without knowledge of the results of the reference standard?

Yes

If a threshold was used, was it pre-specified?

No threshold defined.

Is the reference standard likely to correctly classify the target condition?

Yes

Were the reference standard results interpreted without knowledge of the results of the index test?

Unclear, but likely that the surgeon reviewed the CT scan prior to the procedure.

Was there an appropriate interval between index test(s) and reference standard?

Yes

Did all patients receive a reference standard?

Yes

Did patients receive the same reference standard?

Yes

Were all patients included in the analysis?

Yes

Are there concerns that the included patients do not match the review question?

No

Are there concerns that the index test, its conduct, or interpretation differ from the review question?

No

Are there concerns that the target condition as defined by the reference standard does not match the review question?

No

CONCLUSION:

Could the selection of patients have introduced bias?

RISK: LOW

CONCLUSION:

Could the conduct or interpretation of the index test have introduced bias?

RISK: LOW

CONCLUSION:

Could the reference standard, its conduct, or its interpretation have introduced bias?

RISK: HIGH

CONCLUSION

Could the patient flow have introduced bias?

RISK: LOW

Laiturie, 2011

Was a consecutive or random sample of patients enrolled?

Yes

Was a case-control design avoided?

Yes

Did the study avoid inappropriate exclusions?

Yes

Were the index test results interpreted without knowledge of the results of the reference standard?

Yes

If a threshold was used, was it pre-specified?

No threshold defined.

Is the reference standard likely to correctly classify the target condition?

Yes

Were the reference standard results interpreted without knowledge of the results of the index test?

Unclear, but likely that the surgeon reviewed the CT scan prior to the procedure.

Was there an appropriate interval between index test(s) and reference standard?

Yes

Did all patients receive a reference standard?

Yes

Did patients receive the same reference standard?

Yes

Were all patients included in the analysis?

Yes

Are there concerns that the included patients do not match the review question?

No

Are there concerns that the index test, its conduct, or interpretation differ from the review question?

No

Are there concerns that the target condition as defined by the reference standard does not match the review question?

No

CONCLUSION:

Could the selection of patients have introduced bias?

RISK: LOW

CONCLUSION:

Could the conduct or interpretation of the index test have introduced bias?

RISK: LOW

CONCLUSION:

Could the reference standard, its conduct, or its interpretation have introduced bias?

RISK: HIGH

CONCLUSION

Could the patient flow have introduced bias?

RISK: LOW

Lee, 2014

Was a consecutive or random sample of patients enrolled?

Yes

Was a case-control design avoided?

Yes

Did the study avoid inappropriate exclusions?

Yes

Were the index test results interpreted without knowledge of the results of the reference standard?

Yes

If a threshold was used, was it pre-specified?

No threshold defined.

Is the reference standard likely to correctly classify the target condition?

Yes

Were the reference standard results interpreted without knowledge of the results of the index test?

Unclear, but likely that the surgeon reviewed the CT scan prior to the procedure.

Was there an appropriate interval between index test(s) and reference standard?

Yes

Did all patients receive a reference standard?

Yes

Did patients receive the same reference standard?

Yes

Were all patients included in the analysis?

Yes

Are there concerns that the included patients do not match the review question?

No

Are there concerns that the index test, its conduct, or interpretation differ from the review question?

No

Are there concerns that the target condition as defined by the reference standard does not match the review question?

No

CONCLUSION:

Could the selection of patients have introduced bias?

RISK: LOW

CONCLUSION:

Could the conduct or interpretation of the index test have introduced bias?

RISK: LOW

CONCLUSION:

Could the reference standard, its conduct, or its interpretation have introduced bias?

RISK: HIGH

CONCLUSION

Could the patient flow have introduced bias?

RISK: LOW

Sihoe, 2000

Was a consecutive or random sample of patients enrolled?

Yes

Was a case-control design avoided?

Yes

Did the study avoid inappropriate exclusions?

Yes

Were the index test results interpreted without knowledge of the results of the reference standard?

Yes

If a threshold was used, was it pre-specified?

No threshold defined.

Is the reference standard likely to correctly classify the target condition?

Yes

Were the reference standard results interpreted without knowledge of the results of the index test?

Unclear, but likely that the surgeon reviewed the CT scan prior to the procedure.

Was there an appropriate interval between index test(s) and reference standard?

Yes

Did all patients receive a reference standard?

Yes

Did patients receive the same reference standard?

Yes

Were all patients included in the analysis?

Yes

Are there concerns that the included patients do not match the review question?

No

Are there concerns that the index test, its conduct, or interpretation differ from the review question?

No

Are there concerns that the target condition as defined by the reference standard does not match the review question?

No

CONCLUSION:

Could the selection of patients have introduced bias?

RISK: LOW

CONCLUSION:

Could the conduct or interpretation of the index test have introduced bias?

RISK: LOW

CONCLUSION:

Could the reference standard, its conduct, or its interpretation have introduced bias?

RISK: HIGH

CONCLUSION

Could the patient flow have introduced bias?

RISK: LOW

Study reference

Study characteristics

Patient characteristics

Prognostic factor(s)

Follow-up

Estimates of prognostic effect

Martinez-Ramos, 2007

Type of study: prospective study

Setting and country: Hospital, Spain

Funding and conflicts of interest: not defined

Inclusion criteria: patients with a first PSP.

Exclusion criteria: recurrences of PSP, concomitant lung disease, or patients requiring surgery.

N=55

Mean age ± SD: not defined

Sex: 75% M / 25% F

Potential confounders or effect modifiers: none

Describe prognostic factor(s) and method of measurement:

Once resolution of the pneumothorax had been

confirmed by a chest x-ray, a chest CT scan was performed

between the first and the sixteenth week following the

pneumothorax episode (Asteion helical CT scanner

with 3-mm collimation and a pitch of 5.5 for apex-to-base

scans of the lung parenchyma with a lung filter.

All images were interpreted by the same radiologist, who was unaware of the symptoms, the location

of the pneumothorax, and the treatment used in each case.

Duration or endpoint of follow-up: mean 30.7 months (95%CI: 24-37)

For how many participants were no complete outcome data available?

N (%): 0

no significant differences in recurrence-free

survival were found between patients with or without

bullae (Breslow test, P=.88).

Casali, 2013

Type of study: retrospective study

Setting and country: Hospital, Italy

Funding and conflicts of interest: not defined

Inclusion criteria: first episode of PSP and underwent CT.

Exclusion criteria: surgical treatment, >50 years

N=176

Mean age (range): 27 (14-41)

Sex: 76% M /24 % F

Potential confounders or effect modifiers:

Chest drain (93%)

Bed rest (7%)

Describe prognostic factor(s) and method of measurement:

CT examinations performed before May 2003 were conducted with axial acquisition and typical parameters were 120 Kvp; 160 to 240 mAs (depending on patient size); slice thickness, 1.25 mm; and slice interval, 3 to 5 mm in apical level and 10 mm in other levels, with bone

reconstruction algorithm.

All CT examinations after May 2003 were conducted with spiral acquisition and typical settings were 120 Kvp; 160 to 240 mAs (depending on patient size); slice thickness, 1.25 mm; and slice, 1.25 mm applying bone reconstruction algorithm.

Blebs were defined as thin-walled spaces containing

air of 1 cm or less and bullae were those exceeding 1 cm

in diameter

Duration or endpoint of follow-up: minimum 12 months.

Time to ipsilateral recurrence was 12.8 months.

Time to contralateral recurrence was 41.7 months.

For how many participants were no complete outcome data available?

N (%): Data for 199 patients were recorded. Of these, 8 were lost

to follow-up, and 15 underwent surgical intervention

Reasons for incomplete outcome data described? Not defined

(Adjusted) Factor-outcome associations (include SEs or 95%CI and p-value if available):

Incremental predictive value¹:

PPV: 68.1%

NPV: 6.1%

Huang, 2007

Type of study: retrospective study

Setting and country: Hospital, Taiwan

Funding and conflicts of interest: nothing to report

Inclusion criteria: PSP

Exclusion criteria: no underlying lung disease

N=231

Mean age ± SD:

21.9 ± 4.7

Sex: 93% M / 7% F

Potential confounders or effect modifiers:

Describe prognostic factor(s) and method of measurement:

HRCT of the lung was performed when a pneumothorax

presented and reexpanded after chest drainage. A slice

thickness of 1 mm and a section spacing of 5 mm were selected.

Particular attention was given to the detection of lung blebs or

bullae in both lungs, regardless if currently affected by pneumothorax.

By convention, a bleb is defined as an air collection < 1

cm in diameter, and a bulla is defined as an air collection > 1 cm

in diameter. HRCT scans were reviewed by two radiologists, who

were blinded to the clinical data. The assessment of blebs or

bullae on CT was categorized according to whether presence of

blebs/bullae or not.

Duration or endpoint of follow-up:

For how many participants were no complete outcome data available?

N (%):

Reasons for incomplete outcome data described?

(Adjusted) Factor-outcome associations (include SEs or 95%CI and p-value if available):

Incremental predictive value¹:

Ouanes-Besbes, 2007

Type of study: prospective study

Setting and country: Hospital, Tunisia

Funding and conflicts of interest: not defined

Inclusion criteria:

First PSP, diagnosed with a X-ray.

Exclusion criteria: Patients with a history of PSP and

those with coexisting lung disease.

N=80

Mean age ± SD:

Recurrent PSP (n=15): 25

Non-recurrent PSP (n=65): 27
(SD not described)

Sex: % M / % F

Recurrent PSP (n=15): 93%M, 7% F

Non-recurrent PSP (n=65):

98%M, 2%F

Potential confounders or effect modifiers:Chemical pleurodesis (40% in group with recurrent PSP and 15% in group with non-recurrent PSP)

Describe prognostic factor(s) and method of measurement:

A high-resolution CT scan

of the thorax was performed on each patient during the 2-week period following hospitalization

for pneumothorax. Plain CT scans (lung windows) were performed using a spiral CT scanner. A slice thickness of 1mm and a section

spacing of 10mm were selected. All CT scans were analyzed by the same radiologist (MG)

Blebs were defined as small air collectionso1 cm in diameter as opposed to bullae which are

X1 cm in diameter. Dystrophic lesions were analyzed in both the affected and the controlateral

lung.

Based on the CT findings, three grades were recognized: grade I (minimal lesions) where 0onp2; grade II (many lesions): nX10. This

gradation together with the lesions distribution between both lungs allowed for the calculation

of a score of dystrophic severity10 (Table 1). This score has a maximum of 8 points and a minimum

of 3 points.

Duration or endpoint of follow-up: 92 months

For how many participants were no complete outcome data available?

100%, no lost to follow up.

(Adjusted) Factor-outcome associations (include SEs or 95%CI and p-value if available):

Incremental predictive value¹:

No recurrence (n,%):

BB+: 49 (75%)

BB-: 16 (25%)

with recurrence (n,%):

BB+: 9 (60%)

BB-: 6 (40%)

Study reference

(first author, year of publication)

Study participation¹

Study sample represents the population of interest on key characteristics?

(high/moderate/low risk of selection bias)

Study Attrition²

Loss to follow-up not associated with key characteristics (i.e., the study data adequately represent the sample)?

(high/moderate/low risk of attrition bias)

Prognostic factor measurement³

Was the PF of interest defined and adequately measured?

(high/moderate/low risk of measurement bias related to PF)

Outcome measurement³

Was the outcome of interest defined and adequately measured?

(high/moderate/low risk of measurement bias related to outcome)

Study confounding⁴

Important potential confounders are appropriately accounted for?

(high/moderate/low risk of bias due to confounding)

Statistical Analysis and Reporting⁵

Statistical analysis appropriate for the design of the study?

(high/moderate/low risk of bias due to statistical analysis)

Martinez-Ramos, 2007

Low

Low

Low

Low

Low

Low

Casali, 2013

High

Patients who underwent CT scan may be a specific group.

Low

Low

Low

Low

Low

Huang, 2007

High

Patients who underwent CT scan may be a specific group.

Low

Low

Low

Low

Low

Ouanes-Besbes, 2007

High

Patients who underwent CT scan may be a specific group.

Low

Low

Low

Low

Low