Table 1:

Trialists starting position and conclusions

First author	Start	End	Starting position	Authors’ Interpretation of the results
Izbicki	1989	1991	‘To what extent [MLND] contributes to the chance of cure remains controversial’ [23].	‘… [MLND] is a safe operation that can be performed with acceptable morbidity and mortality rates’ [23]. ‘[MLND] did not improve survival … HR 0.78 95% CI 0.47–1.24’ [11].
Sugi	1985	1998	‘… pulmonary resection without mediastinal lymph node dissection has been considered a palliative operation’ [12].	‘… peripheral non-small-cell carcinomas smaller than 2 cm in diameter do not require [MLND]’ [12]
Wu	1989	1995	‘The usefulness of [MLND] … is still a matter of controversy in the field of thoracic surgical oncology’ [13].	‘As compared with [MLNS] … [MLND] can improve survival in resectable NSCLC’ [13].
Darling	1999	2004	‘Unfortunately, despite the fact that surgical staging of mediastinal lymph nodes is thought to be important, most surgeons do not perform a complete lymphadenectomy at the time of lung cancer resection’ [26].	‘…no difference in local (P = 0.52), regional (P = 0.10), or distant (P = 0.76) recurrence between the two groups.’ [MLNS] [MLND] [10] There was no difference in survival (P = 0.25) [10].
Zhang	2006	2007	‘Compared [MLNS], [MLND] carries the potential advantage of accurate staging and survival benefit. But it may also be associated with increased surgical risks by prolonging operation time, increasing blood loss, and resulting in more complications’ [15].	‘[MLND] and [MLNS] have similar surgical risks and mediastinal staging effect in patients with NSCLC’ [15]. ‘[MLND] had significantly better five-year survival than [MLNS] (55.7% vs 37.7%, P = 0.005)’ [15].

MLND: mediastinal lymph node dissection; MLNS: mediastinal lymph node sampling.