Here is the code sample
cq = c(15.5193589369923,15.6082097993496,15.3048276641115,15.887944383963,15.3813224284544,14.9723432922121,14.8742353464212,15.0448020475332,15.1584221729435,15.3692219904727,15.2369219681739,15.0804950645883,15.0836397511495,14.8821059462034,14.6827696388115,14.5701385743889,14.8506248103639,14.8475325690146,14.7377458445001,14.6258765734272,15.3585770134881,15.2994209401567,15.5178103826596,15.2411668198437,15.3413307248142,15.3645926457095,15.2241340874265,15.7516405898009,15.7683360263607,15.5852354340738,14.7451372367313,14.650625258402,14.7596201108925,15.0504977144055,15.0178091754821,15.100874342289,14.5156700740607,15.0530667717479,14.754595621435,15.5879633065185,15.3449828894141,15.3112460363113,15.232600495493,15.4378070492087,15.1621663266126,16.0120124580213,16.2104534293435,16.2765899877946,17.1446379330444,17.1717364140053,17.0155350105157,15.5218922723681,15.4543443324508,15.5282690363252,15.0202919978723,15.0410524376083,15.1169661551775,15.335220483258,15.3191814464955,15.0679651604846,14.7270263787123,14.70717761566,14.7907442084919,15.8468089268423,15.6714073529734,15.5478017041242,14.6949593095613,14.7537769900696,14.830942214569,15.0820225358985,15.3454125813989,15.304399073517,15.4159319040107,16.1250033895004,15.5359407225865,15.3251900155103,15.1571914994646,15.412721442436,15.913112918988,15.9852823695227,16.0912887332562,15.4897399161851,15.0710262650299,15.3517226832146,17.0001128578501,17.1040579605654,16.9578316599788,15.8842918497549,15.7016383123704,15.8513519332371,16.9420990886101,17.0793832045434,16.9288868492911,14.9127628979216,14.7689529893246,15.0534122173222,15.3185448628303,15.5507864243439,15.3737185073511,15.4350799532271,15.2414612478027,15.361320770232,15.7401140808761,15.8582795450189,15.7634036480016,15.5797995263497,15.9126261329496,15.9256641722586,15.1308493265056,15.2450158090279,15.0699176510971,15.0368959001792,14.8828877909216,14.8852035927172,15.8253506435753,15.8938440960183,15.888311876759,15.4872886586516,15.5492199156675,15.7313291529313,16.5365758222542,16.8386981731158,16.7239280992675,15.9356391540897,15.7383049532238,15.9409000309973,15.2005952554035,15.0390142751348,15.154888655127,14.6373767323354,14.3087397097081,14.3970067065903,14.6453627024929,14.8109205614192,14.6266778290643,15.5170574352528,15.359943766027,15.5869322081508,15.5246550838727,15.4670382654415,15.4211907882731,16.9534561402918,17.4848334482537,17.3182067272327,15.7804318020053,15.86794322314,15.6532944587946,16.543432367992,16.6848617423114,16.8344939905775,15.5212254647114,15.8348559815603,15.6592827767612,15.3027400892518,15.5498124465958,15.8362202772445,14.8415823671167,15.7307379811374,14.8529575353737,16.6466266958983,16.1687733596343,16.0342973266029,14.5976161739123,14.776507726931,14.6780484406283,15.3927619991024,15.3106866267163,15.2920260038624,15.9666798099925,16.2595244266754,16.1035265916681,16.018233002759,15.8460056716414,16.0722176294152,16.2763177549617,16.364250121284,16.2995041975045,16.3975912697976,16.182759197402,16.1164022801451,16.5026752161837,16.2401540005223,16.3715573563274,18.4119769797938,18.1208386122385,18.0068316479116,17.1455993749728,17.0558275544137,16.9150038143768)
sample = c("CD4 LM","CD4 LM","CD4 JC","CD4 JC","CD4 JC","CD4 BM","CD4 BM","CD4 BM","CD4 MC","CD4 MC","CD4 MC","CD4 TM","CD4 TM","CD4 TM","CD4 MM","CD4 MM","CD4 MM","CD4 SRits","CD4 SRits","CD4 SRits","CD4 GV","CD4 GV","CD4 GV","CD4 WW","CD4 WW","CD4 WW","CD4 CH","CD4 CH","CD4 FJ","CD4 FJ","CD4 KS","CD4 KS","CD4 KS","CD4 NG","CD4 NG","CD4 NG","CD4 CG","CD4 CG","CD4 CG","CD4 CSR","CD4 CSR","CD4 CSR","CD4 JM","CD4 JM","CD4 JM","CD4 DF","CD4 DF","CD4 DF","CD4 AM","CD4 AM","CD4 AM","CD4 BP","CD4 BP","CD4 BP","CD4 ER","CD4 ER","CD4 ER","CD4 SRusse","CD4 SRusse","CD4 SRusse","CD4 DS","CD4 DS","CD4 DS","CD4 KJ","CD4 KJ","CD4 KJ","CD4 GD","CD4 GD","CD4 GD","CD4 KG","CD4 KG","CD4 KG","CD4 KR","CD4 KR","CD4 KR","CD4 FN","CD4 FN","CD4 FN","CD4 RM","CD4 RM","CD4 RM","CD4 LA","CD4 LA","CD4 LA","CD4 EC","CD4 EC","CD4 EC","CD4 KW","CD4 KW","CD4 KW","CD4 HB","CD4 HB","CD4 HB","CD8 LM","CD8 LM","CD8 LM","CD8 JC","CD8 JC","CD8 JC","CD8 BM","CD8 BM","CD8 BM","CD8 MC","CD8 MC","CD8 MC","CD8 TM","CD8 TM","CD8 TM","CD8 MM","CD8 MM","CD8 MM","CD8 SRits","CD8 SRits","CD8 SRits","CD8 GV","CD8 GV","CD8 GV","CD8 WW","CD8 WW","CD8 WW","CD8 CH","CD8 CH","CD8 CH","CD8 FJ","CD8 FJ","CD8 FJ","CD8 KS","CD8 KS","CD8 KS","CD8 NG","CD8 NG","CD8 NG","CD8 CG","CD8 CG","CD8 CG","CD8 CSR","CD8 CSR","CD8 CSR","CD8 JM","CD8 JM","CD8 JM","CD8 DF","CD8 DF","CD8 DF","CD8 AM","CD8 AM","CD8 AM","CD8 BP","CD8 BP","CD8 BP","CD8 ER","CD8 ER","CD8 ER","CD8 SRusse","CD8 SRusse","CD8 SRusse","CD8 DS","CD8 DS","CD8 DS","CD8 KJ","CD8 KJ","CD8 KJ","CD8 GD","CD8 GD","CD8 GD","CD8 KG","CD8 KG","CD8 KG","CD8 KR","CD8 KR","CD8 KR","CD8 FN","CD8 FN","CD8 FN","CD8 RM","CD8 RM","CD8 RM","CD8 LA","CD8 LA","CD8 LA","CD8 EC","CD8 EC","CD8 EC","CD8 KW","CD8 KW","CD8 KW","CD8 HB","CD8 HB","CD8 HB")
df = data.frame(cq, sample)
df.res <- lm(cq~sample, data = df)
require(lsmeans)
t<- pairs(lsmeans(df.res, "sample"))
system.time(tc <- confint(t, level=0.95))
The time taken by the confint function is
user system elapsed
10.58 0.00 10.60
I have tried using confint.default but I get an error
tc <- confint.default(t, level=0.95)
Error: $ operator not defined for this S4 class
It's a bit buried in the documentation, but what's slowing you down is the multiple-comparisons correction computations. There's wide variation in the elapsed time for the available methods. See the Confidence-limit and P-value adjustments section of ?summary.ref.grid for details, and decide which method meets your criteria of being both fast enough and reliable enough for your use case ...
adj <- c("tukey","scheffe","sidak","bonferroni","dunnettx","mvt")
sapply(adj,function(a) system.time(confint(t,adjust=a))["elapsed"])
## tukey.elapsed scheffe.elapsed sidak.elapsed bonferroni.elapsed
9.256 0.195 0.168 0.173
## dunnettx.elapsed mvt.elapsed
14.370 1.821