Table 8.

Results of quantitative studies examining effects of nihilistic views of health professionals on medical and treatment outcomes

Study	Health professionals	Outcome	Main findings
Pessimism regarding the use of platinum based chemotherapy for stage IV NSCLC
Jennens 2004 Australia	Physicians, medical and radiation oncologists and thoracic surgeons who saw patients with metastatic lung cancer	Referrals for chemotherapy for stage IV NSCLC	Does not examine the effect of pessimism on referrals - the outcome of interest, referrals for chemotherapy, is included as part of the measure of pessimism
Pessimists vs realists vs optimists (underestimation vs realistic estimation vs overestimation of survival rate for resected stage I NSCLC)
Schroen 2000 USA	Pulmonologists and thoracic surgeons treating adult lung cancer patients		Differences between pessimists, realists and optimists
		Believe in survival benefit in NSCLC for chemotherapy:
		As adjuvant for resected stage I-IIIA disease	p = 0.07*
		In addition to radiotherapy for unresectable locally advanced disease	p < 0.001* lower for pessimists
		For stage IV disease	p = 0.31*
		Believe in palliative benefit for chemotherapy for stage IV NSCLC	p = 0.19*
		Believe in survival benefit for adjuvant radiotherapy in resected stage I-IIIA NSCLC	p = 0.66*

NSCLC = Non small cell lung cancer; *Chi-squared test.